Articles from Stargazer95050

Staying connected while traveling in the EU

nobody@ipernity.com (Stargazer95050) — Sat, 18 Jan 2020 22:40:02 +0000

Stargazer95050 has posted an article:

Earlier, I had posted a blog about the thoughts I put into selecting the right phone & plan for a trip to Tokyo : ipernity.com/blog/stargazer95050/4716358

When traveling to european countries from the US, it becomes easier, as there are very low hardware obstacles. Nearly all modern, UNLOCKED US-phones have sufficient capabilities to connect to the european GSM carriers. There are few (Verizon & Sprint) phones that cannot be used at all, due to CDMA vs GSM incompatibility.

There remains a small possibility of some compatibility issue with some provider's 4G networks. Use FREQUENCYCHECK to see what providers & bands may not work with your phone : frequencycheck.com/compatibility/motorola-moto-g4-td-lte/germany. Avoid providers with 0% LTE compatibility with your phone. If you lack some 4G bands, in most cases it is not a problem in metro areas. It likely only has impact on coverage in remote areas.

New EU regulations eliminated the expensive roaming charges for customers and you can buy a SIM in one country and use it for a limited time in another. With a compatible phone, you can buy a local SIM in a store or order one online and have it shipped to your (US) home address.

WORTH CONSIDERING : Depending on your destination and travel style, you may not need any 4G data at all and public or hotel WIFI may be sufficient.

SOME CAVEATS : typically the period of free roaming is limited. Since you likely will be traveling for 10...30 days, this often may not be an issue. There are plans lasting only 14 days while most last 30 days and a few extend to 90 days.

SOME CAVEATS : often (not always) the SIM while roaming only can make phone calls to its "home" country without incurring extra charges. If you plan to call a cab or your hotel by voice/phone, this could be problematic (not working) or expensive (add roaming charges). You should select a SIM with (local or EU-wide) voice, if that is important.

SOME CAVEATS : not all cards & plans support tethering/hotspot -- in most cases, this is independent of roaming.

SOME CAVEATS : especially seemingly "cheap" cards advertise large 4G data-volume only to bury a disclaimer "3G speeds while roaming" in the fineprint.

IMO this contradicts the EU regulation but if you purchase such a card from the US, it may not apply and you are stuck with that slow speed.

SOME CAVEATS : Local SIMs may actually be cheaper than the (foreign/roaming) SIMs offered online. Ordering ahead of time adds convenience and you don't have to spend time navigating a foreign town to find a store or buying one at the overpriced stores at the airport.

SOME CAVEATS : Some plans & carrier include a SIM in their price. Other carrier offer plans -- and require separate purchase of a SIM. Watch out for expensive shipping charges.

SOME CAVEATS : When roaming, you do not know which network provider is covering you and that can affect coverage & network speed. In remote areas, this can be an important factor (incl compatibility). For my trip to Iceland, I specifically picked a local SIMINN card for that reason.

For my trip to Japan, I decided to have 4G data plan for my phone and ordered it online. OTOH during recent visits to the EU, I chose to buy locally :

ICELAND : I wanted the better coverage provided by SIMINN. 5GB (plus voice) cost ~$25, 10GB (no voice) also cost ~$25 : www.siminn.is/en/prepaid That is not a bad deal and SIM was included !!

PORTUGAL : Using WIFI was sufficient, until I had to call landlords to meet & exchange keys to vacation rentals. 5GB cost 20EUR (~22USD) includes voice-line, SIM and taxes & fees : vodafone.pt/en/products-services/visiting-portugal.html

GERMANY : There too it is not so expensive (compared to US) to get a prepaid card but I think this is DATA-only : 10GB cost 20EUR (~22USD) : www.vodafone.de/freikarten/callya-digital/?icmp=mobilfunk:callya-digital

"Amazon EU roaming" : the cheapest data-only card (with 4G hotspot) sells 6GB of data for $22USD. The cheapest data+voice cost $25USB and has 5GB of data for 4G LTE hotspot. Claims calls to anywhere in the EU, not limited to "home" country.

By comparison a US service : fi.google.com/about/plans cost a minimum of $30USD (plus taxes & fees -- they can add 10%...20% on top of that, may charge extra one-time cost for SIM). For that money, you get a measly 1GB of data. NO TYPO -- it states $10 per GB !!

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Attempting to save money on a data-plan for short travel -- IS IT WORTH IT ?

That question, of course, is very personal but considering the overall cost of a trip, it may be not worth the time to bother about saving approx $20.

You might be able to get a "roaming" SIM for $20...$30USD -- OTOH, if you walk into a local store and pick a SIM with 1...5GB for 30 days, you might get an equally good or better deal and pay $20..50EUR. Possible voice & SMS included.

SAVE TIME : if you urgently need to make reservations or contact a pickup from the airport after your plane touches down ==> buying a local SIM is not for you.

SAVE TIME : by buying a SIM online and have it shipped to your home address before the trip starts. Possibly activate SIM from abroad and have it ready as you land.

SAVE TIME : In Portugal, I was glad the clerk help with the setup of the SIM in store and got it to work quickly. It took me a while to manually get the japanese SIM to work. That was NOT a language issue, as screenshots all showed english characters -- just a steeper learning curve.

SAVE MONEY : Sometimes (not always) the cards sold online for $30 can provide similar service as a local 50EUR ($55USD) card. It also can be that you paid $55USD(50EUR) and you could have gotten same service locally for 25..30EUR.

CONCLUSION :

Looking back, I think the most decisive issue to choose local versus online (US) purchase comes down to the amount of TIME SAVED and the URGENCY to connect again to internet (and voice).

You also may want to add LANGUAGE BARRIER as another reason to favor (US) online order over the local shop. Especially in Japan, I would have had a harder time to find a store selling SIM-card while in US & EU, I can read signs and recognize the various brand names.

Happy trails -- and don't spend too much time online and instead enjoy your stay abroad. On vacation, 1GB of data is a lot -- no need for the 60GB plan.

© Copyright 2020, All rights reserved - Post a link, do not copy or embed. Contact me, if you want to use it in your blog or publication or if you want a print

PS : This is not an INFOMERCIAL and links to any vendors were based on web-search, not any payments. Please use your own good judgement & research.

Staying connected in Japan

nobody@ipernity.com (Stargazer95050) — Wed, 07 Aug 2019 16:22:39 +0000

Stargazer95050 has posted an article:

Many people cannot (or don't want to) imagine life without constant connectivity to the Internet -- even during their vacation. When you travel abroad, you need to make preparations for that.

The MOST IMPORTANT PRECAUTION to take is to check the terms & conditions and (expensive) charges that can arise from using your phone on a foreign carrier's voice or data-network. To prevent excessive charges, make sure you disable all kinds of roaming. Removing your SIM and solely use WIFI is a good idea.

In Europe, legislation has made roaming easier & cheaper for europeans ("Roam like Home") but for Americans or when you travel elsewhere, "roaming charges" still can be an issue, if you are not careful.

CAUTION : In some locations, even using WIFI can incur high charges. Ferries, cruise ships & planes are notorious for such charges. They can be absurdly high e.g. $1...$15 / MB -- that's $1000...$15000/GB !! Compared to the typical $10/GB !!

CHEAPEST OPTION :

Solely using public and free WIFI-hotspots in your hotel and elsewhere is the easiest solution.

In Tokyo, as in many other cities, restaurants and businesses often offer WIFI to their customers at no extra charge. Some show the password, in others you have to ask. Unless you need constant network connection (e.g. online translation services, turn-by-turn navigation, immediate photo-upload), this solution should be enough for most.

NOTE : you wont have city-wide coverage and will have to manually hop from one to the other hotspots and never know where you have the net WIFI connection.

Some transit system offer free WIFI to their guests. In Tokyo, I have seen that but there you first needed to register with a confirmed email. For a foreign visitor, that’s a "Catch-22" since you need an internet connection to register for WIFI but that WIFI refuses to log you in until you confirm you have received the email. Maybe it works, if I had registered in advance. You can do that ==> see JR-rail or Monorail web page.

CAUTION : some providers will follow up with a stream of advertising to your email. Other options are special apps which can locate open hotspots and also log you into them. Numerous reviews point to tracking and much unwanted advertising – currently most free apps do that ☹.

You can try to use a temporary email service to register and later discontinue that email to get rid of all that SPAM -- but providers may recognize popular temp email services and block them.

MOST CONVENIENT & INEXPENSIVE OPTION :

Use your own, unlocked GSM-phone and insert a japanese (data-only) SIM

If you want or need constant connectivity anywhere, you cannot rely on WIFI-hotspots. Instead you can buy a japanese SIM and use it in your own (EU or US) phone -- that costs $20...$50 depending on the duration, data volume & speed you choose. Best of all, Amazon and other vendors ship SIMs to your US address (for free) and you don't have to navigate stores to get one.

Of course, you need an UNLOCKED PHONE with a SIM-slot and you have to check compatibility www.frequencycheck.com (enter your phone’s make & model and the countries you plan to visit, also check different providers !!). For Japan, you need at least one compatible UMTS band and one compatible LTE and be sure the phone supports also at least one of the protocols. Often phones lack in that department. The MOTO G4 passed the minimum requirements : frequencycheck.com/carrier-compatibility/qWyLuP/motorola-moto-g4-td-lte-16gb-xt1625/ntt-docomo-japan and it worked there as promised.

Buying a SIM-card is not a challenge : Either order one ahead of time, have it shipped to your EU or US home and activate it before getting on the plane or buy one locally. Many options and when they say “unlimited” be sure to read the fineprint. Check if the card allows TETHERING. Not all do.

SIMs typically need to be activated via Internet and it is easier to do that from home before you leave e.g. while you wait inside the airport.

Setting the APN in your phone can be done manually – some providers have apps to that but I’m too suspicious and didn’t want to install an app for that.

For my trip, I’ve used this approach and have ordered & received the SIM to the US, did the setup and activation beforehand. Manually setting up the APN is not difficult -- be sure to apply ALL settings shown on the web site. With that, the phone would connect. The first time it took a few minutes until it logged into the NTT-DoCoMo network.

RENTING A HOTSPOT -- “Pocket WIFI”

Renting a hotspot is especially useful, when you travel as a group or family and a shared hotspot provides more connections and higher speeds & data allowance than a SIM + cell-phone. Since those rental hotspots are made for the japanese market, you don’t need to worry about compatibility and won't have coverage & compatibility issues you might see with a foreign cell-phone.

Not surprisingly, these rentals are more expensive than SIM-cards but typically provide more data volume and from what I’ve heard, also faster connections.

I’ve paid $22 for a data-SIM valid for 2 weeks & 1GB of data 4G LTE including tethering and no throttling.

The rentals I have seen, start at ~¥700/day but typically cost ¥1000/day (that’s at least ~6.50 USD/day) and for a 13-day stay that would be $84.50…$120 (versus the $22 for a prepaid SIM).

If you walk around the city and need constant connectivity, you have to carry the extra hotspot together with your phone. Plus extra AC-charger. I decided, this was not convenient for me but can be useful for a family.

NEED A VOICE-LINE ?

It is complicated for a foreigner to get a SIM with voice service and your phone may not be compatible with the networks in Japan. If you really need voice, I suggest you read this www.getaroundjapan.jp/archives/2313 plus additional research.

Likely it is easier to rent one directly at the airport or book them in advance and have it shipped to your hotel or pick up at the airport.

Nowadays you likely can reach your contacts via SKYPE or other messanger apps and can chat using a data-only SIM.

NOTE : Chatting on a phone in public, especially on public transit, is a NO-NO in Japan. I wish that same courtesy would apply on US transit systems !!

UPDATE : Now I have seen a provider offering a combined voice+data SIM : www.mobal.com/japan-sim-card. The minimum cost is ¥7500 and cover 30 days and gives you at least 7GB of LTE-speed data. Data volume is reset at the 1st of each month and during a 2-week visit, you might use 7GB high-speed data in the last week of the month plus an additional 7GB during the first week of the following month.

WHY NOT rent a hotspot ?

* You need to carry one extra gadget with you in addition to your phone. Plus one extra charger & cable.

* Prices are ¥700 …¥1000/day or more. That’s approx. $6.50…$9.00 USD/day while a prepaid data-SIM can be had for ~$20…$50 and it is valid for 2 or more weeks. Typically hotspots offer larger data volume than the SIMs, especially the low-cost offers.

* When properly set up, a phone with a prepaid SIM will work as you get off the plane and switch on the phone. If you need to message someone to pick you up, that can save time. You cannot pick up your rented hotspot until you have made it through immigration, luggage pickup and customs. This delays the message by 30...90 minutes, possibly more. Similarly upon departure, you have to return the hotspot (mail or at a drop-off or counter) before you pass through security while the SIM can be used while you’re waiting for the plane to be boarded. In case of delays or other issues, still having this connection can be very helpful.

* Some SIMs remain valid for 12 months and you can refill them for your next trip.

PROBLEMS when using a rented hotspot (hotpot as well as tethered SIM)

My iPhone was tethered via WIFI to another phone acting as a hotspot using the JP data-SIM. The iPhone decided it was a great idea to download iOS12 while being in Tokyo and it saw a seemingly "free" WIFI connection. That OS-update instantly drained my entire remaining data volume. It would not have done that via its own cellular connection.

I curse all automated update features as they can cause high extra charges due to roaming and excessive data usage.

OTHER CONSIDERATIONS (hotpot as well as SIM)

US-Streaming services don’t like people viewing content outside the US, even their own paying customers. Blame the movie studios for this archaic rule. Sometimes a VPN can help but Netflix & Co are putting more and more of them onto a blacklist.

Hopefully you’ve got better things to do in Japan than streaming US videos.

Also your webpages and search results will change when in Japan. Naturally Google shows you results in japanese and many travel websites also recognize your location and present you japanese version of their sites.

One solution is using EPIC-browser and enable the integrated VPN and set it to match your home location. AFAIK, that workaround is not working for Netflix streaming but it does help reading US sites and access travel sites in english.

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PS : This is not an INFOMERCIAL and I have intentionally not included links to any vendors, especially as I have not tried other alternatives. Please use your own good judgement & research.

© Copyright 2019, All rights reserved - Post a link, do not copy or embed. Contact me, if you want to use it in your blog or publication or if you want a print

Build your own GPS tool -- update 2015/09/24 & 2019/02/12

nobody@ipernity.com (Stargazer95050) — Tue, 12 Feb 2019 09:31:05 +0000

Stargazer95050 has posted an article:

SOME OSMAND DISAPPOINTMENTS : SOME OSMAND DISAPPOINTMENTS : he-shelf items for hikers are GARMIN handheld devices -- and I have used two (older) models. The new devices lack SD-card interface and the ability to download custom (open-source and free of charge) maps.

There are some legacy devices I like -- but they are hard to find and often are expensive, among them the "eTrex 30x", the "eTrex Vista HCx" & "Oregon 400". The eTrex is slimmer and has more buttons and the "x" model also has a SD-card. The Oregon has a touch-screen and includes a micro-SD slot. If you want to quickly set way-points without browsing a screen, the older model with buttons is easier to use.

These devices can be quite expensive -- often costing >$300, or $250 for used one, in moderate condition. DO NOT buy old Vista (non-HC) models -- those lack USB and use RS232 and you have trouble connecting & uploading data.

With newer maps, you can prolong the life of your Garmin -- see garmin.openstreetmap.nl

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While I dislike the high, monthly costs of the cell-phone plans and hate the built-in surveillance by Google, Apple & AT&T, I admit, the hardware of these phones has made a lot of progress and the price of some of them is tempting. For this project, I plan to use an ANDROID PHONE -- without a SIM-card (airplane mode) and without setting up any Google account on the phone.

At first, I will attempt to do this without rooting the device -- later, I want to kick-out some of the annoying (Google & Samsung) software and only a rooted device can do that.

WHICH DROID DEVICE IS THE BEST FOR THIS TASK ?

You cannot answer this question unless you specify some of the goals & constraints. This is my list :

SD-card is a must (cheaper & more flexible than built-in memory) to enable side-loading of maps ==> that eliminates all iFruits and many new phones.
SD-card doesn't have to be accessible from the outside -- I have no plans to pop-in a card from my camera
replaceable battery is a very desirable feature but not a must-have ==> replace battery instead of entire phone once the capacity degrades
shirt-pocket-size, nothing larger than 5" ==> inconspicuous & easy to carry, one-handed operation
To avoid incompatibilities, the phone should be running at least Android V4.x -- there still are phones & MP3 players with Android 2.3
Screen resolution isn't a major factor and 800x480 may seem outdated. To view maps & photos on a 4" display, this moderate resolution is sufficient and 260dpi isn't a bad resolution. For a 5" display, 1280x720 can do the job. It also improves battery life
while I have little use for the "phone" portion, I will pick a GSM-phone just in case I have to make calls here or in Europe.
Like every other phone, it also has a camera but that isn't going to be important to me.
no 2 year contract or (mandatory) registration at a store
I am willing to buy used phone -- 2...3 year old technology is not as outdated as you may think.

There were some contenders -- and first I looked at the mini-tablets & MP3-players. The expectation was those should cost less than a cell-phones but in many cases, they cost the same or more, while using an outdated Android OS and a mediocre screen. (e.g. Galaxy Player 3.6" & 4.0", likely has no GPS)

There were VERY ATTRACTIVE OPTIONS -- I dismissed them for their 5"...6" size. The $200+ price-tag for a 5" ASUS ZenFone 2 is tempting. Those phablets are useful for work but won't fit my shirt-pockets when I'm on vacation.

Many tablets boast about "location" they are careful not to mention GPS -- because they have none. That makes them ineligible for this competition.

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You may come to other conclusions -- I like the price/performance ratio of a Samsung S3 Mini ($100, refurbished G730A, no contract, GSM unlocked world-wide, supports US & EU GSM-2G & 3G-frequencies, updated with Android 4.4) and that is going to be my starting point. I am supercharging this phone with a fast 32GB SD-card -- slow SD-cards ruin the usability and freeze the GUI for minutes when handling maps (I've experienced that myself)

Android V4.4 causes some problems : You will experience a known Android issue with the WRITE_EXTERNAL_STORAGE permission: Android V4.4 has changed the rules and from now on, no application can write to the SD card anywhere outside its new standard folder Android/data/[PACKAGE-NAME].

~~NOT SURE if that would~~ FORTUNATELY it does not prevent the PC from copying new OSM maps into that location.

Software options listed here wiki.openstreetmap.org/wiki/Android and wiki.openstreetmap.org/wiki/Comparison_of_Android_applications and from those want to find the one that suits me best.

With my intention to stay out of the Google-verse, I also will need a tool with APK download from outside the Google store. The intrusive store & update-policy are two reasons I want to avoid it. My S3 demanded to install a new version and that ate a lot of my scarce memory. So I've reset the phone and never touched any Google app again.

Also, a rooted device cannot access that store -- I want to add my own HOSTS but can't do that on a stock phone.
While I don't object paying for good software, I prefer a direct transaction, skipping Google's store
Using offline maps on the SD-card has the highest priority for me -- OSMbased apps are the best options I've seen.
Also desirable is a built-in / offline point-to-point routing & navigation feature -- again OSM-based apps can do that (limitations include length of the trip).
There are several different map formats, some BMP, some vector-based. Not all apps support all formats. Vetor-based demand more CPU-power but zooming in is better and usually they are smaller (my investigation is ongoing)
record the track in GPX & KML-format
quick way to set waypoints and record photos & voice-memos from within the same app
ROUTE PLANNING & driving directions: The phone would only be used for the point-to-point, single day trips while I would use the laptop to lay out the much longer roadtrip

GPS Essentials : It is "free" but the ads are very annoying. My goal is to stay out of the Google-verse but only there can you purchase the $5.30 add-on to switch-off the ads. Other drawbacks :

It can use maps while offline -- but those have to be inside the cache and that means you have to slowly cruise across the area of interest beforehand. That may not be a problem when you follow a predefined route. When you are on a spontaneous roadtrip without network, that cache-based map is useless. I have not yet seen an option to use a map from the SD-card and the app also cannot be moved there.

NAVIGATION & ROUTING : Offline routing is not available

CACHED MAPS -- there is only one (hidden) way to download a larger range of maps with a single click. It only works with MAPQUEST and after you select that as a source, there's a download button which will download the map shown on the screen plus the tiles for the next 6 higher magnification. To download all of California in detail, you still need to scroll around, download, wait 10 minutes, and repeat.

With a large cache, the tool becomes very slow and the OS often asks if the app should be killed because it is not responding. I decline, wait and after a long wait of several minutes, it usually comes back to life.

OsmAnd : Also is a seemingly free tool -- the limit is 5 maps you can download and the full version costs $6.00 payable via Google store.

The behavior was odd at times - and there is no manual control when or which map it will use. Besides the global map, I installed CAlifornia and that is very detailed. Also, I've downloaded the entire map for Germany and when I zoomed in, it wants to download yet another map for the local german state I was looking at. Same happens with France. What's the use of the large overview maps -- which now account for 1.2GB of data and 2 map downloads. There is a workaround to the download limitation -- it requires patience (manually download files from download.osmand.net/rawindexes using a PC) and some extra steps (rename, unpack, copy to SD-card)

NAVIGATION & ROUTING : Offline routing is one useful feature - 200...250km range is the limit OsmAnd can handle -- quote from FAQ : If the app does not show a route after 7-8 minutes of calculation time, it is worth to considering to place waypoints (pick e.g. places on motorways). Seriously -- 7...8 minutes

The app requires a GPS signal to plan a route and it starts at your current position. That's nice when you are driving a car but not helpful to plan days ahead of time.

Normally it keeps the display on permanently but you can send OsmAnd to the background (e.g. home or press power-button) and after that, the screen will power-off as usual & GPS still collects the track data. I HAVE NOT TESTED NAVIGATION IN THAT MODE -- voice commands are inaudible while driving and when I use navigation, I rely on the display.

OsmAnd also has the "Nanny-mode" enabled by default -- keeps nagging about exceeding speed limits even slightly. I didn't ask for that and on freeways everybody drives 5...10mph above the limit. Good luck finding the option to disable it -- it is there.

Locus : The free version is only available through appstores. (Amazon, Google & Samsung), the $7.50 PRO-version only via Google. No direct APK download from source I trust.

mapFactor Navigator free : It is a utility you can install on your PC and it doesn't download the Android software but it offers a simple interface to select and download free OSM maps.

The app is available only via the App-Store, no direct APK download -- there also is a free PC version for the PC and one for old Win-CE devices. The PC version is designed for touch screen and has the routing features & offline maps I want. Maps can be downloaded easily. There are separate maps for each state, only France & Germany each are sliced into 4 separate quadrants to keep the file-size down.

Navit :

Nogago :

Be-on-Road :

WAZE / Google MAPS : Even if I would drop the "No App-Store" rule, these still would have a hard time to qualify. Like other tools, they will use their persistent cache to store maps and therein lies the problem. The cache uses the (smaller) built-in memory, not the large SD-cards. And you need to browse the entire area of interest in high resolution BEFOREHAND. That's only practical on a city or county level -- not on a vacation / state-wide level. AFAIK there's an option to download the map to cover the area in a 10 mile radius -- happy scrolling even if you want to cover only a small metropolitan area. Impractical for a vacation / roadtrip.

And I want no part in the permanent surveillance Google imposes on the users of their products -- especially always-on Android apps.

update 2015/09/24

GPS Essentials is out of the race -- it cannot pre-load the maps the way I want and it became extremely sluggish and crashed when I used large (cached) maps. and those covered only California -- I want maps to cover half of Europe !

LOCUS and others -- since I don't want to join the Google-club and burden my "phone" with even more updates and Google+, all these apps aren't accessible (except through dubious sources)

OsmAnd -- this app at first didn't woe me but it does a lot of the stuff I want and it thankfully hasn't the Google restrictions. Despite dire warnings, it is possible to shift the maps to an external SD card and use the PC to download new maps and add them to that directory. That step much easier than it sounds. HOWEVER I am not using any Android/Google/Samsung tools -- instead I plug that card directly into the PC -- a hurray for the memory slot and external card.

Galaxy S3 Mini (G730A) + 16GB SD-card -- you can setup OsmAnd to place data on the SD-card and if you use a fast card, the S3 can quickly redraw the map even when after you have installed a large number of maps.

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CONCLUSION 2015/09/24

The Open Street Maps are good and a combination of cheap phone + OSMAND can make for a good GPS tracker and map-tool. The NAVIGATION / ROUTING feature is another story. Tall buildings in San Jose & San Francisco caused GPS blackouts and navigation results with OSMAND were unreliable. Maybe if the antenna had been outside the car, reception would have been better.

In all, I would say the OSMAND-navigation can be useful for point to point navigation but it isn't capable of planning multi-day trips and optimizing long routes. The README even states limitations for distances exceeding 250km !!

DISAPPOINTMENTS :

In OSMAND, seasonally closed mountain passes are unavailable for automatic routing all year round -- if you trust the computer, it will send you on a 200+ mile detour. And there is no option to override this. OsmAnd isn't the only tool with this bug.

Another goal of my (re)search was to find a tool which would let me quickly record waypoints without many menus & clicks -- none of the apps I have tried can do that :-( . The winner in this category still is the GARMIN eTREX (without touchscreen).

NOTE : if you convert the OSM-maps to Garmin, you get excellent maps but you loose search & routing abilities garmin.openstreetmap.nl . Ony $$$ conversion-tools maintain that kind of information.

UPDATES 2019/02/12 :

It has been a long time since the last update and I have been using OSMAND ever since. But I have switched from the very compact Galaxy S3 Mini to the much bigger MOTO G4. The deciding factor for the Moto G4 was better support for 4G & LTE and foreign providers while traveling. A 5.5" display is bulky in a pocket but offers a bigger view of the map while navigating.

The MOTO G4 has a more up-to-date Android release -- and that has frustrating limitations when it comes to SD-card access and data-exchange. But one can work around those.

And after some time, I got used to the massive size of the phone -- I still prefer something in the 4.5...5.0" range. Given the features, excellent compatibility domestic & abroad (including Japan) and the low price, that phone was a great pick.

SOME OSMAND DISAPPOINTMENTS : During the visit to Japan, issues displaying local street names were a problem. In Japan they use the same characters as in chinese alphabet but they are pronounced differently and have different meanings. OSMAND apparently used a chinese translation to convert japanese to english conversion of street names. That occured even when I disabled automatic conversion. Street (english) name shown in the map would not match the (english) name shown on the signs.

OTOH, the maps did correctly show the streets and I could use it to record my tracks and for navigation.

SOME OSMAND DISAPPOINTMENTS : Searching for addresses in US cities also proved to be problematic -- especially when you wanted directions to a very specific address including house number.

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© Copyright 2016, All rights reserved - Post a link, do not copy or embed. Contact me, if you want to use it in your blog or publication or if you want a print

Building an ASTROnomy camper-van -- Part #2a

nobody@ipernity.com (Stargazer95050) — Tue, 20 Feb 2018 03:22:25 +0000

Stargazer95050 has posted an article:

The main part of the existing layout of my ASTRO-VAN is the variable bed-frame (see more at ipernity.com/doc/stargazer95050/47262742 .

That size determines the rest of the available space. The cabinets on the passenger side are useful, but they do limit the storage. Compared to my 1st ASTRO VAN, where I could transport wide boxes next to the bedframe this is a big change.

It turned out that these boxes became too heavy to load or transport and now, I divide & conquer ==> e.g. store smaller items in these cabinets can be beneficial but they are an obstacle to storing multiple bikes.

This Divide & Conquer strategy also means, I need to find room to store multiple, smaller bags or boxes. And there are other factors -- some of which seem fixed but are worth reconsidering :

STORAGE -- bicycle. As shown in this photo, transporting one bike inside the new van's cabin is possible, as long as the mattress isn't wider than ~80cm. Transporting two bikes would require them to be partly disassembled. In both cases, you must remove the bike(s) to access the cabinets or storage you have underneath the bed.

Alternative : it is possible to add an external bike-rack -- this new van has the necessary hitch at the rear bumper. That, of course, limits your access via the rear doors while carrying bikes. And you have to protect the bike(s) from the harsh elements, vandals & thieves.

STORAGE -- below the bed : currently clear space offers only ~25cm/10" in height and this can be sufficient for items like surf boards (prev. owner was a surfer). For trips to Burning Man, I have used large, flat boxes to protect clothes & food from the dust. Those fit underneath that frame, but you cannot stack them. EVEN WORSE, my astronomy equipment and ice coolers are taller and don't fit beneath it.

That (low) cargo height allows for a comfortable position to sit on the bed without bumping your head. That's the trade-off of raising to provide storage for larger items -- hanging the bed from the ceiling really avoided many of these issues.

The insulation in the new van further lowered the ceiling compared to the original Astro van.

STORAGE -- raising the bed by max 10 inches : that's adding a lot of extra storage space below the bed frame but removing 10" of headroom also makes it a lot less comfortable to sit. I like the idea of using the cabinet as a table for keyboard & laptop and have the monitor semi-permanently placed there. If the bed is too high, the position isn't comfortable. Currently, I think ~45cm/17" height is large enough for my equipment -- raising it by bed by 5", max 7 inches.

The mechanics of raising the bed & mattress that high are another serious issue that I have started tackling. Below you see a setup to test the modifications and evaluate the changes. It illustrates the possible changes (7" raise) and allows to compare different options.

While experimenting, I found one more useful change -- add a "shelf" between the wheel-well and the rear door and use that to store the telescope tripod. This shelf will make use of unused space and at the same time remove obstacles for easier access.

STORAGE -- driver-cabin : there's one Coleman-cooler model that fits perfectly in the isle between the driver's & passenger's chair. In addition, bags can fit behind the chairs and the wall. The Coleman Box is one obstacle in removing these bags quickly.

The existing bedframe & support leg also are in the way ==> one mre reason to raise the height of the bed.

POSITIVE : that prevents quick smash & grab thefts. NEGATIVE : unloading them for astronomy observation also is a hassle. I'll opt for easier access and -- if really needed -- add some locks & cables to secure the stuff.

STORAGE -- modified driver-cabin & cargo wall : the previous van didn't have a divider behind the driver's seat and that simplified utilizing room between bed & driver's seat for storage. The new van has this wall and it divides this space into two.

One radical option would be to remove this wall -- make the new Vanessa more like the old one and free up space between the bed & driver's seat. OTOH, that wall is useful for other purposes : attach hanging storage or even shelves, adds shade & blocks view, attach curtain.

The divider wall behind the passenger seat has been in place in both vans and in the old van I have found it mostly beneficial. This installation differs and in this van the wall is ~5" further to the rear and that takes away a lot of space.

And I took the drastic step of removing this wall -- you can see the the newly available space :

The new plan calls for a small shelf or other storage to be place in the gap between bed & driver's seat. I even have experimented with sliding the bike in there -- and it will fit !! see www.ipernity.com/doc/stargazer95050/47291564

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Building an ASTROnomy camper-van -- Part #1

nobody@ipernity.com (Stargazer95050) — Wed, 17 Jan 2018 14:53:14 +0000

Stargazer95050 has posted an article:

Determining the "ideal" size of a camping & astronomy van takes several attempts and a lot of refinements. Or read some research and find useful feedback from others. This is my 2nd attempt and you can read why I picked this model.

If you just want to transport astronomy equipment, nearly any car will do. Since one important purpose is astronomy, not only do I want to be able to transport the bulky equipment but at the same time, I also want to get some comfortable sleep (before or after the observation). Plus, on some roadtrips, I want to bring along a bicycle (ready to use, no assembly required) and still want to have room to sleep in the car and -- at best -- also carry astronomy gear.

Besides what a camper can do, it also is useful to define what your campmobile doesn't have to do :

-) On vacation, I like to eat out and want to avoid washing dishes ==> no need for a kitchenette.

-) And I am willing to stay in a motel when I want to soak in a bathtub ==> no need for RV-like features like a shower.

-) Also I am willing to forgo the port-a-potty and will use restrooms in a diner or gas-station along the way. Adding a chemical toilet is comparatively easy, if you plan ahead and have storage with sufficient height.

You could compare these requirements to a TENT ON WHEELS -- and that is a good description. With that, there's no need to carry propane gas for cooking or heating or extended water supplies. Keep this in mind when you look at the result -- your choices will differ and that will change your design.

Standing upright is not a requirement but sitting upright on the mattress is really desirable. Being able to walk bend down instead of crawl on your knees (as in the pickup's campershell) is a big plus.

Packing the bike in one piece horizontally will require a lot of space and occupy room for the bed. OTOH, if a van is tall and has a long cargo area, rolling in a bicycle upright is a possibility and that still will leave room for a bed. Also keep in mind, if you want to unload the bike in the city, it can be difficult to do that through the rear door with a car parked behind you. A sliding side door helps in such situations.

A few cars & models I have to excluded from the beginning :

-) cute VW busses don't have enough horse-power and busses in good condition nowadays are expensive collector items.

-) AFAIK, you can't fit a bicycle in one piece inside the original VW-bus while still setting up the bed. If you're willing to remove the front wheel and turn the handle-bars, fitting the bike will be easier. I do not count the newer T4 as a classic VW-bus.

-) Caravans & even SUVs don't offer the convenience of a comfortable mattress while still having storage for bulky astronomy equipment. These cars lack headroom to sit upright in the bed. Some compact SUVs are too short to have a full-length mattress in the rear. The model I had rented was long enough as it was the XL-version with the optional 3rd row seats. Still, you cannot fit a bike ("as is") into that SUV while still having room to sleep at the same time. Same goes for the Subaru Forrester & Outback.

A pickup with a campershell was my first (non-astronomy) choice and there I was able to fit the bike inside and have room to sleep -- not at the same time but that was enough for trips to Burning Man. Upon arrival, I reconfigured the interior and had room to sit upright on the bed. To do that, I had to unload most of the equipment and therefore this solution wasn't suitable for roadtrips (unless you stay every night on a designated campground). But it was a great solution for a week long stay in Black Rock desert.

Excluding SUVs, pickups & cars. That leaves one category : VANs.

And when I looked around, I found the "latest" (2000 and newer) CHEVY ASTRO to be a great fit -- the GMC SAFARI is a re-branded ASTRO and it also would have met my criteria :

-) 200hp is a good amount of horsepower -- the iconic VW-bus is smaller & lighter but with 50hp... typ 90hp underpowered when fully loaded. Even the 4-cylinder 120hp pickup was sluggish uphill and acceleration was barely noticable on I-80 heading up the Sierra towards Tahoe.

-) Chevrolet sells ASTROs with 2 rows of passenger seats and windows all around. For my purpose, I chose the CARGO VAN option with fewer windows and an empty cargo area. Some owners have modified the passenger vans for camping but I dislike having windows around for everyone to peek into the inside. Having rear windows helps keeping an eye on traffic. Same goes for the window inside the cargo door on the side.

-) Vans come in many different sizes and my limit was ~190 inches / 4.8m. That length is similar to medium cars & compact pickups (like my old S10) and fits in garages.

The Chevy EXPRESS is the ASTRO's successor and is 30...45 inches (1.0...1.5 meter) longer. Many craftsmen & delivery services like that van for this reason but parking such a long van is more difficult. It can be too long to park inside garages & strett parking. Other van builders have used the EXPRESS for their camper conversion because of the extra length.

-) Height also is a factor but unless you have raised the roof, that rarely isn't an issue. Vans usually are < 2 meter (79 inches) tall while restrictions typically are 7...8 feet height (84...96 inches). Camper-vans with fold-up roofs or over-cabin beds are a different story.

Vans like the ASTRO are popular and even while no longer in production, there still is a large stockpile of spare-parts, new & used. (e.g. Craigslist, Pick-n-Pull, junk yards). Mechanics are familiar with this model. That keeps the costs of maintenance & repair in check.

-) There are "miniature work vans" like the Ford Transit Connect or the NV200 and people have converted them into campers. I found the interior cargo room too small for my purpose. If you don't have store bulky cargo below the bed and/or plan to bring a bike, these vans can be an alternative. Even used they cost much more because of their much lower age & mileage.

With vans popular in the US, I am not the only one thinking about such camper conversions. Without good carpenter skills and a workshop & tools, my own "1st generation conversion" was very functional and did fit all my needs : Transport equipment and a comfortable hanging bed.

Other people had more skills and time and I found a successor ASTRO VAN with better camper features than my 1st DIY approach. The cabinets on the passenger side will allow me to store some equipment in there instead of packing it inside boxes. That simplifies access.

This photo also gives you an impression of the room for the bike plus available storage below the bed. Unfortunately, the mattress is an odd-size (discontinued model from Ikea), much narrower than the off-the-shelf items. That makes it harder to get a replacement and new covers & sheets. That bedframe can be expanded to some degree -- e.g. pick a mattress for 2 persons (if you give up the in-car bike storage). Since this van has an optional trailer-hitch, adding an external bike-rack is easy.

The photo also hints at another -- unexpected -- advantage of this new setup :

Sitting on the bed and placing the 24" monitor on those cabinets, there's no need to move that gear to the outside during observation. That will save time during setup and later when packing up. It also helps to avoid bright lights of a laptop-screen polluting the observation site -- the screen doesn't leave the van. Hanging a thick, black cloth is enough to avoid further light pollution.

Once the setup is done and imaging sequence has started, there's no need to stare at the screen and I'm going to enjoy the view outside. my telescope-mount has a hand- control that let's me make adjustments without sitting in front of the computer.

Other conversions : offtracktravel.ca/tag/astro-van-conversion

There is a community of fans : www.astrosafari.com

This concludes my PART #1 -- Selecting the right car / van

Next, I plan to write more about the details of what goes into a DIY camper/astronomy van. Things like increased storage & headroom, extra battery & chargers, heating or not. And other tips & tricks

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© Copyright 2018, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication

Easy Backup & Rescue -- for Tablets & PCs

nobody@ipernity.com (Stargazer95050) — Thu, 30 Nov 2017 23:50:31 +0000

Stargazer95050 has posted an article:

Running BACKUP usually is a dreaded task, many computer users neglect. And to make it worse, restoring data also isn't always easy. When your OS is damaged (or hijacked by ransomware), it isn't able to do its job and restoration may seem impossible. (Windows)-Tablets with their fewer IOs and small disk-space make backup even more challenging.

Unless you are prepared ....

PREPARATIONS : with new PCs & W10-tablets, manufacturers & Microsoft don't want you to be able to boot other software and you need to change BIOS-settings to disable that feature. Look in the UEFI settings -- there you may find a "legacy boot" and other security-options that currently lock you in.

PREPARATION #2 : Especially tablets lack USB IOs and a physical keyboard. You cannot press "F2" or "F12" or "DEL" to enter BIOS and make changes to the boot sequence. At that early stage, the touchpad or touchscreen also don't work. Instead you will need a USB-hub with at least 3 slots to connect a KBD, a mouse and one or more USB drives. If you add an Ethernet-port, you are able to download latest Antivirus definitions and other updates.

It is difficult to backup (or restore) the OS while it is running ==> therefore my suggestion is to avoid that hassle and save the status that is written onto the HDD. For that, I previously have used a (very) old version of DRIVECLONE V2.1 and it did a really great job of creating a snapshot of the any of the partitions (incl MBR, all partition-data & OS) and it only took a few minutes. (Note : my OS partition intentionally is small : ~35GB).

To backup the much larger DATA partitions, I use a different strategy -- there I don't have to worry about concurrent access, locked data and other access issues.

DRIVECLONE added a dual-boot loader and you could boot Windows by default or DC to backup or restore a partition. Recent changes to MS Windows (e.g. GPT boot) made DRIVECLONE incompatible and now I am looking for another, equally simple yet powerful backup tool to capture & restore a snapshot of the OS (*).

While old-fashion desktop PCs & BIOS have a lot of compatibility and often even can boot from physical CD/DVD, new laptops & tablets lack many features & USB-ports, making backup more complicated.

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Of course you first need to have a LARGE USB-drive. These drives already have been formatted and contain only a single partition. To perform both BOOT & BACKUP from a single USB-drive, we need 2 partitions on one drive.

Using DISKMGMT you can delete the original partition and create two new ones : one 500...1000MB FAT32 partition for the BOOT-image. Plus a large FAT32 or NTFS partition to store the backup data. Optional : create directories, one for each device. CLONEZILLA will create additional sub-directories with a timestamp -- but if you backup multiple devices, you cannot rely on timestamps alone.

CLONEZILLA : This is a well-known tool and it can create & restore SNAPSHOTS of partitions and entire hard-disks. The IMPORTANT detail is that CLONEZILLA cannot store the backup data on the same partition it is booting from ==> that's why I advise to reformat the USB-stick to use 2 partitions. New Linux releases can write to NTFS and that reduces issues with max size of files (e.g. FAT 32 has 2GB limit).

GPARTED : You don't want to repartition a drive without first running a backup and once repartitioning is done, you may need to restore data. Having CLONEZILLA & GPARTED in a single Linux-image seems like a natural fit. To my surprise, it wasn't easy to combine the tools into one build :-(( One uses GUI, the other is a text/console application.

DRBL-LIVE : This is the ONLY distribution which combines both GPARTED & CLONEZILLA & it can boot from a SD/USB-memory & it can store the backup images on a 2nd partition on that same USB-card (if you follow the instructions above). There are other releases combining GPARTED & CLONEZILLA but they don't get the job done for one reason or another (usually booting the tablet).

The combination of USB-drive, TUXBOOT & DRBL finally worked (GPARTED & CLONEZILLA) on all my PCs & W10-tablet.

DOWNLOAD TUXBOOT EXE-file tuxboot.org
DOWNLOAD DRBL-live ISO-image (Gparted & Clonezilla are included) : drbl.org
RUN DISKMGMT & DELETE existing partition from USB stick
CREATE new partition #1 on USB : choose FAT32 and 500....2000MB size and mark that partition as ACTIVE. This will hold LINUX OS
CREATE new partition #2 on USB : choose FAT32 or NTSF -- I am using NTFS because Linux can read & write NTFS and you don't have 2GB size limitations per file and can use large drives.

Microsoft officially doesn't support FAT32 partitions larger than 32GB (it works with W7 & W10 but not XP32). NTFS allows to creates files > 2GB while FAT32 has size limitations. exFAT is another option but lacks backward compatibility.
NOTE TO XP32 USERS :

It seems that having 2 partitions one physical USB-drive is not supported in some XP32 versions, especially mixing FAT32 & NTFS..

On my old XP32 PC, I cannot always see all partitions. XP32 also has issues with drives > 32GB unless they are NTFS. No exFAT support.
RUN TUXBOOT and install DRBL-live ISO on USB partition #1
USB partition #1 as ACTIVE (it should be done, might need DISKMGMT to check or activate if necessary)
optional : before your backup, create sub-directories on partition #2 -- e.g one for each device
TESTING !!

Booting from USB on a tablet is especially tricky -- e.g. none of the partitions created by YUMI would boot on the (W10)tablets while it worked on all other "real" PCs & laptops

There is only a small remark to this -- at times, DRBL's default setting resulted in an unreadable 640x480pi display. Upon boot you can choose "OTHER --> KBS" and with that selection, the OS-loader picks a higher resolution and so far I had no trouble with those.

The RUNNER UP : MultiBoot_USB (Pendrivelinux.com)

MINUS : Doesn't boot on the W10 tablets. Boots on all other laptops & desktops
PLUS : Installation is easier -- just install that ISO onto Partition #1. No need for extra TUXBOOT steps. You still need to create two or more partitions (or use 2 USB dries). You cannot save the BACKUP-images onto the boot partition.
the ISO-image contains the more recent releases of GPARTED & CLONEZILLA.
TBD : The SATA-drive with 2 partitions is recognized by XP32 while other USB-drives are not. Not sure why that is the case -- maybe SATA vs USB. Both drives combine FAT32 bootloader & NTFS data partition.

CAUTIONARY TALES :

RUFUS will erase your ENTIRE USB-drive -- even when it contains multiple partitions. If you have multiple partitions, the checkbox "Quick Format" won't prevent deletion of the other partitions !!
YUMI worked really well and it can combine different ISO-images into one boot partition. For reasons unknown (yet), the tablets refused to boot those images while desktops & laptops worked just fine !
USB-drive & USB-hubs : It is unlikely to happen to a small USB-stick but when you use a USB-to-SATA adapter to backup larger drives, you better be aware of the POWER CONSUMPTION.

A USB2-port can provide max 5V x 0.5A (2.5W). A single port may be able to provide more power, especially when all other ports are idle. A single SSD may need up to 10W (peak). Attaching a SSD behind a unpowered hub with a USB-KBD & USB-Mouse can cause the SSD to fail randomly (due to power failures).

ALTERNATE SOLUTIONS

Combining the OS-BOOT & STORAGE on the same USB-drive simplifies the handling as you can plug a single USB-stick into the tablet/laptop. If you have 2 or more USB-ports (or add a USB-hub), you can choose to use 2 USB-sticks and separate the OS-BOOT & STORAGE. .

OTHER CONSIDERATIONS

With a desktop and laptop, you always have a keyboard and can press "F11" or any other key to enter the BIOS or BOOT-menu. With a tablet, you may not have that many USB-ports and you need a hub to connect the KBD, maybe mouse plus 1...2 USB drives. From my observation, W10-tablets BIOS can boot from USB even if there is a hub -- YMMV.

Always be mindful of the power-consumption of USB-devices connected to the same port -- sporadic errors or unusual long access times are a signs of brief power-failures (which cause devices to reboot and likely loose data). A self-powered hub helps to avoid such issues.

INCOMPATIBLE BUILT-IN PERIPHERALS :

The tablet & laptops are designed to work with W10 after it has booted & loaded all required drivers. But not all peripherals work during bootup or have suitable Linux-drivers. Most commonly you will not be able to use the built-in (Micro) SD-card as a boot-device. It may not even work with Linux after booting.

In one extreme case, even the laptop's touchpad would not work after booting various Linux versions and I had to rely on external USB mouse.

SIZE & SPEED : The old DRIVECLONE V2.1 sure is fast -- both in terms of booting and saving data. If you enable compression, it is really slow because at the time, there were no multi-core processors to accelerate compression. Your compressed image will be approx 50...60% size of the original data but it take 3x times longer. CLONEZILLA's default-setting take advantage of modern multi-core processors to accelerate compression and as a result the image also is 50%...60% the original size (and SWAP-files are removed) and the backup time is longer but not dramatically.

The overhead of compressing the data can balance the time to write the extra data -- and that is especially true when you save to a slow medium like a USB-card.

SAFETY & SECURITY : The old DRIVECLONE did one task -- it copied the data. And AFAIK, it did not CHECK the written data. And there is no option to encrypt the backup image. Adding a verification step after writing the image to me is a worthwhile effort. And having the ability to encrypt the backup can be an important feature as well. CLONEZILLA has both of those options -- verify is on by default, encryption requires an extra step to define the passphrase. (I have not tested how encryption slows down the backup or restore)

EASE OF USE : When booted directly, CLONEZILLA can use mouse and keyboard. The GUI is text-based but you can use the mouse to set/reset the various options and click onto buttons. All the actions also can be done via keyboard, TAB will move the "cursor" forward to the net field, SPACE will toggle an option and ENTER will finish the entry and proceed to the next step. The DRBL image provides a working copy of CLONEZILLA but you must use it solely through the keyboard interface.

Having a backup & repair solution on one stick was the goal of this exercise. And for the most part, it succeeded. With a 64GB Micro-SD card in a tiny USB-stick, I can backup the OS-partition of all my PCs & tablets with the exception of the company-provided laptop. That partition and amount of data exceeds the 60GB available on that card. Backup of that laptop has worked fine using a USB-to-SATA adapter and a comparable SW-setup.

(*) WHY A SNAPSHOT and not a regular or incremental backup ? The answer lies inside Windows and the concurrently running tasks and the files that are locked to prevent interference. It gets worse when you attempt to restore files while the system is running.

When you capture or restore a snapshot of the OS while it is _NOT_ running, all of the above issues vanish.

A snapshot of the (saved) OS partition also can save & restore settings hidden from the user (e.g. hidden registry data). This method also is more resilient to virus attacks as the image and backup code can be independent of the OS & data.

(**) WHY A SNAPSHOT : After a virus or ransomware attack has damaged your OS, you cannot rely or trust the OS (if it still works). It is best to completely wipe it off the disk. Which coincidentally restoring the snapshot will do.

Sometimes Window OS refuses to boot to reasons other than virus -- restoring a recent snapshot often is the quickest fix.

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So you want to -- remotely control your SLR (for astrophotography)

nobody@ipernity.com (Stargazer95050) — Tue, 17 Nov 2015 22:58:20 +0000

Stargazer95050 has posted an article:

There is a divide in the astrophotographer community and you find people using specialized CCD sensors and optional motorized filters -- this is the top-of-the-line approach and they often use very specialized software and $$$$ cameras.

Many others use a dSLR, and they divide between Nikon & Canon and I don't want to hear about which camera is better. You must choose the right software and be sure to check if the software really supports your particular model and what limitations it may have compared to the newer models & software.

General purpose tethering software

digicamcontrol.com is one tool which supports Nikon dSLRs. Open-source & free is another advantage. and now they've added support for Canon as well

breezesys.com/products.htm sells tethering software but you need to buy different product for Nikon & Canon.

Nikon & Canon also sell their own tethering software (Nikon Camera Control Pro 2 & Canon EOS Utility). The big image-editing packages from Adobe have some tethering functions and PhaseOne Capture One also offers such a feature. Here is a more extensive overview : tethertools.com/tethering-software

stark-labs.com/DSLR_Shutter.html serves a very specific purpose -- it allows a PC to let (mainly Nikon) dSLR take exposures longer than 30 seconds. These cameras limit exposures to 30s EXCEPT for MANUAL BULB mode and with a remote cable release and some adapter, a PC can mimic that. the SW has no image preview or other functions.

At the time (2011), the solution by Breeze was the one I liked best and especially the added feature of realtime green-screen overlay made it attractive for use in a demo photo-booth. It also allowed to adjust focus and later perform focus-shacked images. The license of this is problematic and even as a legitimate owner, I cannot re-install the software again. support told me I need to purchase a new $175 license.

Nowadays I would take a closer look at kuvacode.com/smart-shooter ($50, 30-day trial) and oxfordeye.co.uk/tetherPro ($50, no trial period)

Software specific for ASTROPHOTOGRAPHY

Why use a tool specially designed for astrophotography you want to know ?

You can do without -- but it makes life easier in a number of ways, especially when you connect a telescope mount and other equipment to your laptop as well.

-) control the telescope movement directly from the same GUI -- no need to switch between programs

-) send image data to other tools -- e.g. plate solver to determine the position of the telescope

-) help with tasks -- e.g. aid with mechanical polar-alignment

-) help with tasks -- e.g. provide feedback on focus & sharpness

-) help with tasks -- e.g. pause exposures when mount is moving (dithering, meridian flip, loss of auto-guiding tracking)

Astrophotography software to tether a CANON dSLR

One popular software is "Backyard EOS" and it has a reasonable price. For astrophotography, you will want the $50 premium version to be able to control your telescope mount and have the other features. The standard version costs $35USD.

My preferred tool isn't BYEOS -- I favor APT. ideiki.com The reason is more historic than the lower price of 12.70EUR (< $15USD). APT supports seamless interface with AstroTortilla (freeware plate-solver) while at the time BYEOS did not. (Now it has caught up). Furthermore, APT has good support for ASCOM-cameras in addition to dSLRs and BYEOS at the time was lacking that feature. APT supports my Starlight Express and I had no reason to switch.

Both, APT & BYEOS can control a mount but that doesn't mean, you cannot use the software without one.

Sequence Generator Pro has a much more complicated GUI than both APT & BYEOS : mainsequencesoftware.com $100USD. If you are willing to use a more complicated GUI while out in the field, it has some useful extras. Especially the $40 MOSAIC-wizard sounds like a very useful addition.

At $100 it costs as much as BYEOS plus BYNIKON together -- and SGP supports both camera families at no extra costs.

My biggest complaint about SGP are the large number of entries which makes this tools barely usable on the 1366x768 screen of small laptops

NEBULOSITY is another software to support both Canon + ASCOM-cameras and at $100 for the new V4, it also is cheap by astronomy standards. stark-labs.com/ nebulosity.html . Unlike APT & BYEOS, Nebulosity does little to integrate the whole image capturing process (slew, focus, guide, etc. ... ) and instead it has more sophisticated post-processing features.

Astrophotography software to connect to a NIKON dSLR

There now also is a BackyardNIKON -- and it has been approx a year since I have tried it. It is time I try again.

There is no version of APT or Nebulosity which supports Nikon dSLR and Sequence Generator Pro I discussed in the section covering Canon.

I've not seen any astrophotography software solely designed for Nikon without having a Canon counterpart. Smart-Shooter 3 and Tether-Pro possibly can do all the astro-photography image acquisition work and you can handle the mount with an optional, separate tool.

What else do I need to start with tethered astrophotography

The biggest investment is a dSLR -- preferably one with LifeView support other the USB connection. And many cameras can do that without the need of $$$ software. Here is a table : digicamcontrol.com/supported_cameras or check if you like APT (Canon only), Smart-Shooter or Tether-Pro better.

If you are looking for a new camera, consider a model with a flexible rear-LCD. While that is not a must and tethering can eliminate some inconveniences, flipping up a screen really can make observations much more comfortable. The basic up/down tilt is important while a screen with full tilt & rotate (articulated LCD) is a nice to have feature. You will be using the LCD during setup before you start connecting to your laptop -- my 2 cents.

The next accessory you need is a simple (6ft...10ft) USB-cable. As a precaution, I use TWO cables : a short cable which plugs into the camera plus a long one to connect to the laptop. If anyone stumbles over the cable, the two cables separate and (hopefully) there's no damage to the camera, connectors and laptop.

Without this fail-safe, such an accident yould damage the laptop or tip over the telescope + camera.

Additional batteries to power the dSLR are a must and I recommend using a battery-grip. The many long-exposures usually done during astro-photo sessions are taxing the built-in battery. Now add to this the power needed to stream live images to the PC and you can see the need for added power.

This can be a simple vertical grip battery pack or a dedicated 12V converter. 2...3 hours often can be done on a regular battery, and often a battery grip is sufficient for my ~5hr observations. Cold weather decreases battery life -- it also decreases my willingness to stay out there & freeze.

With a motorized mount, the need for battery power increases : ipernity.com/blog/stargazer95050/630825

While we're talking about battery power, your laptop also deserves some attention -- 2...4 hours usually isn't a problem but for a 8 hour night-shift, you usually need to add some booster. It can be a car battery + AC-inverter or a Li-Ion pack. And don't forget, the laptop often powers accessories via the USB ports.

Another important accessory beginners tend to forget is a place to put the laptop.The camera is on the tripod and you have the cables & accessories and now there's no way to place your laptop. In may cases you can improvise and bring a cardboard box, a folding folding-chair or camping table. A larger surface makes it easier to use a (wireless) mouse -- I'm using a trackball which requires only a small footprint. Others may use the trackpad and don't need extra space.

For casual astrophotography, you can use your tripod & (ball)head but when you want to aim accurately, you are better off with a geared or a 2-axis tripod head. And as your exposure times and focal length increase, you should be looking towards a motorized tracking EQ-mount and that will lead you the advantages of dedicated astro-photohraphy software tools.

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So you want to -- power a telescope & camera

nobody@ipernity.com (Stargazer95050) — Sat, 09 May 2015 19:19:50 +0000

Stargazer95050 has posted an article:

UPDATE May 2015 : If you have read it before, scroll down to UPDATE #1 & UPDATE #2 section of this article.

It all started with just a small 12V block battery and an extension cable with a cigarette-lighter plug at the other end. While I hooked this up to a telescope with a matching adapter cable you can use this same battery to power the AstroTrac and some of the small EQ-mounts. With a typ. power consumption of 0.3A, this 4Ah block would be sufficient to drive these mounts for one, ro two sessions without recharging. The only big problem I've encountered with this solution were the clips to connect to the battery's contacts. They weren't strong enough and I had several occasions where the mount accidentally lost power.

Another problem, and that partially is my own fault because I didn't recharge after every use, is loss of power to the mount because the battery was drained. The mount has no under-voltage alarm and at some point it just quietly stops. To recharge that battery, I used the car battery charger I already owned. There are smaller chargers available.

UPDATE #2 : This Lead-Acid battery cost ~$30 and has ~50Wh capacity. A Li-Ion battery with similar capacity currently costs $100, it is smaller, weighs less. But many power-packs cannot provide the high peak currents this block battery can because they use small cells & DC/DC-converters to generate 5V over an longer timespan.

A 12V battery can power other accessories besides the telescope -- but that becomes a bit more tricky. SLRs for example, they don't use 12V as their input voltage -- CCTV cameras and astronomy equipment usually do. WATCH CAREFULLY -- you don't want to fry a $2000 camera in an attempt to save $100. Different vendors, even different models all have different voltage & power requirements. Let alone different connectors & batteries. Nikon cameras even refuse to work unless the battery as a special chip inside. 7.5V...9V are common voltages and 3.0...5.0A, The D3 needs more power and requires 5A @ 13.5V.

My solution -- I've made one only for the Canon 650D -- utilizes a no-frills, 3rd-party battery grip and I've implanted a tiny DC/DC converter that has just the right electrical specs and by sheer luck can be squeezed into the room originally reserved for 4 x AA batteries. With a bit of soldering & wiring, this dSLR now runs on 12V battery or a 12V AC adapter. It is a more rugged solution than using a purely mechanical adapter and leave the DC-DC converter unprotected.

Thanks to power users draining their smart-phones & laptops, a new breed of gadgets emerged and I took advantage of those "Refueling Stations". Compact, high-capacity NIMH or Li-Ion batteries, with built- in chargers and occasionally even with adjustable output voltages. Those "tanks" are a welcome -- but expensive -- option as they have a higher capacity, often include a display to gauge remaining charge and replace the external battery charger with a built-in one (you still need a small AC- adapter). Instead of bare contacts, these devices have built-in plugs and an array of adapters to fit many different devices. For use with my astronomy gear, I still had to invest a bit DIY work but that was now limited to customizing cables and "standardize" them to all use the same type & size of connector.

When you pick such a battery pack, it is important to also look at the maximum output current these devices are rated for. Since they have built-in electronics and are intended to recharge other devices, the peak current may be insufficient to power the mount when it starts up both motors. Especially if you hook up more gear, that output current issue will be more serious. With a regular lead-acid battery, that usually isn't a limiting factor.

This issue of maximum peak current deserves more attention as the number of 12V-powered items increases. 1A...1.5A peak for the small EQ-mount usually isn't a problem for these "intelligent" battery packs. With a mobile, yet complex astrophotography setup, you have a couple of devices hungry for 12V DC power. When you add this all up, the power requirement very quickly will exceed the typical 2A or even strong 4A threshold. Here are some examples

telescope mount : typ. 0.3A...0.9A, peak ~1.5A for medium, >4.5A for bigger EQ-mounts
(main) imaging CCD camera : greatly varies, up to 4A. mine requires ~2A
dSLR (via 12V adapter) : not specified,
Adaptive-Optics / OAG : not specified, estimate 0.5A, short peak might be 2A
Dew-Heater : greatly varies, max output exceeds 10A ...15A
CCD- / dSLR cooler (in case you camera hasn't a built-in cooler) : 2...6A
Laptop (either via AC-inverter or custom DC/DC converter) (< 100W)

alternative : small PC + external monitor (< 120W)
autoguide camera and other accessories (via USB-hub) < 1.5A @ 12V
motorized focuser (also on USB)

The Dew-Heater's power supply clearly belongs into a different category, together with the small PC + monitor. For once, they are significantly larger than the rest but they also are a lot less sensitive to variations and even big power spikes won't necessarily crash the system (the tiny-PC is not as robust as a laptop). At the same time, they are also more tolerant to voltage changes as the battery drains.

All other components are in close proximity and are used in conjunction and therefore it makes sense to combine the power-supply needs & cables. In my case, the typical power requirements can be ~4.5A but hopefully the camera won't be needing 2A all the time. The peak current is critical since a drop in voltage will cause all the USB logic & the telescope mount to reset -- often unnoticed. And I estimate my requirements (no laptop or dew-heater) to be ~6A and that is beyond the capacity of many "intelligent" battery packs I have seen. Despite its massive capacity and $200 price, peak current is "only" 4.75A : BiXPower-42500mAh -- many other Li-Ion solutions have a much lower peak current.

For "tethered" use in my driveway, I now have a 12V/8A power-supply. It has the same size connector than the cable coming from my heavy 12V car-battery. And if I travel light (SLR instead of CCD-imager), I can still use the lightweight NIMH or Li-Ion battery pack.

Another area that requires power -- but often is overlooked and a source of many, seemingly unexplainable errors -- are the USB devices and their drop in power [from own experience !!]. In many cases, the laptop can power the devices you directly connect to it. But in an environment like a telescope setup, you quickly need a hub to connect them all (distance as well as number). Several of these devices require varying, at times large, amount of power, and if you are not careful, these spikes in the power demand can exceed the USB limits and will cause the whole USB bus to crash. At home, you would pick a self-powered hub and plug the supply to the outlet in the wall. My DIY solution is more compact and uses 12V DC.

It appears, the telescope & astronomy accessories have the common sense to use the same size connectors for all the 12V loads. It is a "2.1x5.5mm" and when I add the term "CCTV Camera" search results get a lot better : 2.1 x 5.5mm. These connectors also fit the CGEM mount but tolerances there are quite large. The rubber band you see here adds tension and prevents the cable from sliding out. There is some risk in using this type of connector -- the 19V laptop power-supply uses the same size ==> careful not to mix up the different voltages. And you can accidentally create a short-circuit while plugging a connector in. This might cause permanent damage and even if not, it can cause a reset to all attached devices. Say goodbye to the telescope's alignment. There possibly are connectors with better separation of the two contacts

Anderson "PowerPole" connectors can avoid that issue but to attach your cable, you need a special crimping tool ($40 and up).

The grand-finale for my mobile setup is this DIY- build "Juice-Box" I've tailored to my needs. It houses the heavy bulk of the power supply section -- fortunately this box has wheels. And the size is just right : (more about "VANessa"). Storing a car-battery inside a box isn't a big accomplishment but to make this my 120V & AC power hub, I've added a few useful extras :

regular car battery -- just the right size to fit this box
400W AC-inverter attached to that car battery (powerful -- but noisy fan)

can power "all" : laptop, monitor and many battery chargers
a powerful charger for that car batteries (up to 15A) -- requires AC.

Literally cut it in half to save space : /stargazer95050/19370915
embedded the chargers for my SLRs and other accessories batteries :

==> can recharge them while driving, less clutter
hookup the "Juice-Box"-battery to the car's 12V DC

==> recharge that while driving

MISSING : automatic disconnect. I must pull the plug manually
lot's of storage room left inside this box
moveable 100W AC-inverter (silent, fanless) when low noise is more important than power (e.g. overnight recharging while sleeping)
when closed, the lid has 4 cup holders, a flat surface and looks just like a regular icebox.
even when lid is closed, I can connect an external AC extension cord, thanks to a small incision I made (input to charge or output from DC/DC-converter)
this box is heavy but can be rolled up to a more distant site thanks to the wheels. Most often my extension cables are sufficient to provide 12V & DC-power without removing the "Juice-Box" from the car. (less back-pain & quicker too)

So far, that 400W inverter has produced more noise than results -- the much smaller & silent 100W converter was sufficient nearly every time. Only when in a extreme hurry and needed to recharge 1 or even 2 laptops plus SLR batteries, the 100W output was insufficient. While driving, I now keep the 100W inverter easily accessible and use it to power GPS Navi or up to two small gadgets or the laptop without the annoying wizz from a cooling fan.

Providing power to the components is one part of the effort. If you travel, the issue of packing, safely storing and keeping track of things is just as crucial. You don't want a missing cable to ruin your trip. Since my favorite method of transport is a car and roads are bumpy & curvy, it is worth spending time on preparing for that as well. Furthermore, when planned carefully, you can quickly pack & unpack all your gear in between shoots. At times, I even carry the accessory-"tray" into a motel room to recharge all batteries over night. The recommendation I have is not to pack too many items into one box (gets too heavy) and possible "invest" a dollar or two and buy a pack of freezer bags to each hold one cable (avoids unwanted entanglements, one bag for the TINY stuff). Label each bag and when you pack, you easily can check your inventory. My setup includes a long (green) AC extension cord, jumper cables (just in case) and room for several AC poer supplies & chargers.

One more 12V accessory that you might need -- but not very often -- is a small camping hair-dryer. Not to get the dew out of your air but instead to de-dew lenses, eye-pieces or telescope front elements. A slightly warm breeze can remove the dew without you touching the surfaces. This can be especially beneficial if you already have aligned the mount and are imaging. You don't want to use too much heat and also be careful not to drain your battery -- DO _NOT_ hook that up to a small battery or NIMH unit as those usually cannot deliver the 10A...15A needed.

Also be careful not to drain your car's battery with your astronomy gear. It may be tempting to avoid buying & carrying a dedicated heavy battery but gettnig stuck because the car won't start is not worth these savings.

Also, is not enough to have all these power-supplies & (rechargable) AA & AAA batteries, you still need a large collection of different (non-rechargeable) batteries :

SR-54 / GP189 / L1131 (x3) are used in one of the illuminated crosshairs
GPA76 (x2) are used in the other illuminated eye-piece -- at least both illuminators use the same screw so I can swap them as needed
CR2032 (x3) inside the electronic angle gauge
SR44 (x1) for the digital caliper I use to measure the focus position
CR123A are used in various laser collimators, flashlights and lamps
9V block to power the manual focus motor controller and also for the DVM (Multimeter)

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Update #1 :

Not everyone has the time or know-how to put together a DIY power-supply for a SLR. There are off-the-shelf solutions but those usually require more components. A battery with an AC-inverter plus an AC-adapter to generate your camera-specific voltage and a mechanical "dummy-battery" adapter or custom connector for the camera. The battery + AC-inverter can be cheap and high capacity -- they are heavy and found as automotive accessories or "Power-Tanks" from astronomy vendors. Or you can pick a more expensive and more portable model designed for (fashion) photographers on location to power their flash-strobes -- for example the "Vagabond Mini". $300 for an 8Ah model. OTOH, you can get 18Ah capacity for ~$120, if you pick one of the heavier "Jumpstarter kits" from the automotive section.

The AlienBee's / Vagabond units are designed for smaller loads than many of the automotive units -- that isn't an issue until you decide to add a laptop or other accessories. Another criteria that is often overlooked is the acoustic noise !! -- often the AC-inverters use high-pitch fans and the Vagabond is no exception. Good designs minimize the noise and use the fan based on temperature -- the cheap car accessories usually don't have this. I don't own a AB Vagabond, so I can't tell how annoying their sound is, my Jumpstart unit is annoying, even when idle and gets worse with increasing load ==> I'm not using it any more.

The issue having a noisy fan in the AC-inverter bothered me a lot. It is no fun to sit at a stargazing session and have that dentist-drill sound in your ear. Or get annoyed by that sound while driving & recharging a laptop or other accessories. Fortunately, there are AC-inverters WITH NO FAN and they still can produce sufficient power for most tasks, including powering a laptop. To accomplish this, these units need sufficiently large metal surface. If quite operation is important, so far the best solution I found is a 100W AC inverter. You will have to add your own 12V battery or hook it up to your car's cigarette lighter.

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Update #2 :

Batteries have increased in capacity and their reduced size and these improvements have trickled down to other products. You now can find a huge selection of portable "power-packs" delivering 5V via a USB connector but the choices for 4A @ 12V are much more limited. Given the power demand of a motorized mount, there is a trade-off between price vs size & weight. A cheap car battery can exceed most of these power requirements but it is awfully heavy.

eBike batteries are tempting ($300, 300Wh, 5lbs) but their proprietary connectors make adaptation difficult and you need a DC/DC converter to get the 12V.

Other models also have high capacity. You pay ~$300 for 220Wh (4lbs) and it gives you 15V and up to 4.7A to power the EQ-mount. As an alternative, you can switch to 19V to recharge a laptop.

There's another category of Li-Ion batteries I find suitable for in my astro use. The vendors claim those can jumpstart a car (I doubt that !!) but with a small hack-job you can can convert them for other purposes. DO THAT AT YOUR OWN RISK. You gain a very compact, light-weight battery ~~with 50...60Wh capacity~~ only 42Wh and the strength to deliver high peak currents. Charger is built-in, but it isn't fast. Cost ~$90, 42Wh, 3lbs

The photo shows the modification I did to one of the $90 models ==> I cut off that extra protective circuit -- it interfered with my use. After that I replaced those clamps with two pair of cables and different plugs. This battery has powered the power-hungry EQ6 mount plus attached dSLR for several hours (1/2 night). Not too bad for such a low-weight unit and this can be sufficient for occasional observations.

The battery claims 12.000Ah capacity and that likely refers to the 3.5V cell voltage and results in 42Wh capacity -- that's a poor price/performance ratio.

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Update #3 :

Other Li-Ion batteries can deliver sufficiently high peak current to power the EQ-6 mount _OR_ a laptop _OR_ a CCD camera and has a respectable 120Wh capacity. The cables don't need a hackjob to fit the other tools and $150 for 120Wh is a better deal. Output voltage is adjustable in increments between 12V....20V and meet popular notebook demands. Various adapter plugs are included.

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A virtual astrophotography shopping list

nobody@ipernity.com (Stargazer95050) — Thu, 26 Mar 2015 16:20:38 +0000

Stargazer95050 has posted an article:

The MOUNT -- I wrote about that before /stargazer95050/748671 And to start with, currently I'd go with the iOptron ZEQ25 because of its ability to support bigger telescopes the initial investment will last longer -- $850. OTOH, if you are certain in the future you want to use larger reflector tubes and heavier accessories for astro-imaging, skipping the smaller ZEQ25 mount can save you money in the long run. The iEQ45 is a step up in both price & weight but still a very manageable & portable unit (20lbs, up from 11lbs for the ZEQ25, CGEM or Atlas Pro are 40lbs). These larger mounts are in the $1500...$2000 range (tripod included).

Based on my past experience, I now always order at least one extra counter weight or an extension for the CW-shaft. Often the S&H is lower when combined with the mount and it also eliminates frustration when you add some accessory and suddenly can't balance your mount + telescope + camera + accessories.

12V power to the mount : In most (but not all) cases, the delivery includes a AC-adapter + cable and often also a 12V cigarette lighter adapter. For your first experiments (at home), the AC-adapter plus some 30ft AC-extension cord is all you may need.

Hooking up the mount to your car's battery is a risky proposition -- especially if you are alone away from busy roads. Draining the battery that starts your car never is a good idea -- if you're lucky you quickly find a friend with jumper cables. Also, car batteries can provide immense amount of current in case of a short and that can destroy equipment unless you add a protective fuse. I have several suggestions on how setup your own 12V power supply : /stargazer95050/630825

The glass -- to get started, a good (triplet) refractor is IMO the best choice, even if you crave a big reflector. The larger magnification, collimation procedures, much narrower FOV & heavier weight all require more experience (and stronger mount etc) until you get good results. A refractor is more user friendly and with 700...900mm focal length provides a very noticeable increase in magnification over your SLR lenses.-- read /stargazer95050/748795

For example, the Explore Scientific 102mm f/7 ED Triplet (714mm) appears to be a good deal @ $1500. There are more triplets in that price range e.g. the Orion EON 110mm ED f/6.0 (660mm focal length).

Refractors are getting considerably more expensive as the focal-length & aperture increases and 900mm focal length & 120....130mm aperture seems to be the upper limit for affordable enthusiasts scopes (< $3000, similar to good f/2.8 Nikkor lenses.)

Naturally, you can spend a whole lot more on a telescope with similar specs -- just like a Leica vs Nikon vs Tamron or Sigma lens. There are quality differences but you have to decide, if those are worth a few thousand dollars more.

There are less expensive (doublet instead of triplet) options costing $1000 or less -- if you want to use your telescope for photography, buying higher quality from the start saves you money in the long run because doublets have visual & color errors. They try their best to reduce the effect, you likely you will upgrade. (just as with SLR lenses, to the keen eye, there are differences.)

PS : As you shop for your telescope, look what mounting rings & rails are included. Similar, the vendors use different feet to attach finder-scopes -- making it more difficult or expensive to re-use items.

PSS : And carbon-fiber tubes seem to have backfired -- those tubes weigh nearly as much but the natural insulation causes thermal imbalances and air-current and those have a negative impact on the result.

the (LOSMANDY-style) RAIL : You need some mechanic to attach the telescope to the mount and two standards have evolved and mounts like the iEQ45 support both. One is a narrower "Vixen-style" dove-tail. If you want to mount heavier lenses, a wider "Losmandy D-style rail" is the better choice : Losmandy-dovetail-universal-plate. In the past, I had ordered rails from ADM at a similar price but they lack that flexible pattern. Geoptik & Telescope-express offer some unique options but the dollar exchange rate (plus S&H) make them quite expensive.

UPDATE : the ZEQ25 only supports Vixen rails and some telescopes come with Vixen rails by default -- great for you. From the mechanical view, I find the D-style superior, especially when you use heavy lenses. I have equipped all my OTAs with the same type of "D"-rails -- that comes at a price and some extra weight, while it also brings more flexibility /stargazer95050/32924839. For a "starter kit", a ZEQ25 + light-weight Vixen rail & scope is nothing to frown upon. When you upgrade your mount, be sure to choose a dual-width dovetail saddle capable of supporting Vixen- & Losmandy-D rails.

FINDERSCOPE (plus accessories) : I started with a $100 Orion 9x50mm but the rubber ring to hold the front of that scope's tube wasn't stable enough and I had to adjust it every time I touched it. Therefore, later I added a pair of rings with screws ($50, Stellarvue). My DIY combo still cheaper than the Stellarvue scope and it has some advantages : /stargazer95050/19790563 THIS gives me a much wider range of adjustments !!

A more expensive 60mm finderscope : www.stellarvue.com/f60m2.html -- less DIY, inter-changeable 1.25" EPs, fine-focus, fasters (f/3.75) lens. Still requires extra adjustable rings ($50 extra). It may also be suitable as a guidescope, the Orion is not. That whole Stellavue package adds up to ~ $250.

An alternative I have now added is the 70mm Multi-use finder" -- you can use it with a camera for guiding & as well as with visual eye-pieces : www.ipernity.com/doc/stargazer95050/37284232

From 2" telescope tube to Nikon / Canon bayonet : There are some adapters made as one piece, I prefer that for improved stability -- can't find that link. You can use a 2-piece solution : a T-ring (simple thread) to SLR adapter (bayonet) and add to this a 2" nosepiece with the matching T-thread.

optional Light-pollution filters : Chances are, you live in or close to a city and all those street lights, car lots, stadiums & suburban homes emit light -- and that is reflected back at you by the atmosphere. You can see the effect as orange glow in the sky, even when you are dozens of miles away from any town. In theory, you can vastly reduce that by filtering out those very narrow bands of light associated with the most common forms of streetlights. In practice, these filters aren't as narrow as you wish and they also dampen overall light throughput. And a quality Light Pollution Suppression (LPS) Filter comes with a price tag between $150...$200 or higher.

Nothing beats really dark sky and after a long time of hesitation, I've added a 1.25" LPS filter -- no miracle cure but it improves contrast by filtering out some light pollution. The LPS is no replacement for long drives to dark sky sites. It can help your imaging in suburbia (you still need more post-processing & longer exposure times). Is it worth the $150 ?? -- IMO that depends on how often you can save time & gas and image from your backyard instead of a more remote location.

Other filters : As a beginner, you won't need those with one exception. SOLAR FILTERS Many filters are aimed at advanced astronomers. Other filters, especially variable POL filters or ND-filters, are for visual observers to reduce the brightness of the moon.

Solar / ERF Filters (don't confuse with solar Ha / H-alpha filters) : "Don't look directly at the sun" is a common warning. Solar -- energy reduction -- filters are designed to enable you to look directly at the sun with your eyes or camera by eliminating harmful UV & IR rays and massively reducing bright light (13...16 f-stops !!). You may have seen them as foil in the eclipse observation "glasses". Be very careful and remember to also add a similar filter to your finder scope : search/photo?w=315163&q=ERF

Attaching your dSLR to the mount : Just because you have the intention to use a telescope doesn't make your other (SLR)-lenses obsolete. The mount + SLR + wide-angle lenses complement the telescope. For widefield views without startrails, use one of your lenses and let the EQ-mount eliminate the field rotation. $20 for the small adapter you see here : /stargazer95050/32907293.

You do not need to attach your tripod head to an EQ-mount -- the mount can point at any location you like. The caveat is, you may see tilted landscape in the foreground -- and that's why adding a tripod head or a lens with a collar can be useful. It is neither difficult nor expensive : /stargazer95050/32924839 -- if you have a rail, all you need is a 1/4" Allen screw.

TRIPOD versus extra PIER or optional Telescope-BUGGY : the tripods that came with the mounts are very suitable -- the iOptron 2"-tripod allowed for an easy upgrade to add DIY adjustable feet extensions : /stargazer95050/29051567. Sadly, the smaller tripod legs of the ZEQ as well as Celestron's legs can't be upgraded that easily.

The idea of putting the heavy mount onto a cart appealed to me and I ordered one : /stargazer95050/19370235 but it failed to be useful to me. Either the terrain was too steep or too rough for the buggy or my setup was close enough to the car.

The pier proved to be more successful -- the 48" model may be a bit too tall with a large reflector but it helps to avoid collisions with long refractors : /stargazer95050/30571979 and /stargazer95050/30311293 The shorter 42" model has less clearance and for visual use, the 48" may be more comfortable

The iOptron pier can be transported quickly but cannot adapt to uneven terrain. Other "piers" have adjustable legs -- just like tripods. Not truly a pier but a lot heavier than typical tripods and with more clearance to avoid collisions : skywatcher-heavy-duty-pier-tripod.

Shopping Cart ($20) -- instead of a Tripod Cart ($350) : while adding wheels to move the assembled tripod + mount proved to be futile, adding a smaller (shopping) cart to move parts of the equipment proved to be "priceless". /stargazer95050/19813205 . With some more DIY modifications, this cart became mobile my "Astro-HQ" : /stargazer95050/30107697 _&_ /stargazer95050/27637353

12V to AC converter : The one I recommend is the FAN-LESS model. The noise of these fans is driving me crazy and the models without fans provide 100...150W. That's sufficient for most of my tasks -- laptops use 60W...90W (recharging + laptop on). Turn off the laptop and you can recharge several additional different items.

For urgent backup & recharge I happen to have a 400W noisy converter -- I learned the lessons the ~~hard~~ noisy way. At times, the 400W is more important than the noise.

12V to 5V concerter : If you have the 12V-to-AC converter, you can use the regular (brick) power-supply to recharge your equipment. when you travel, you can save weight & volume by leaving many P/S at home and use a single unit to recharge all. Good idea if you drive by car, not so good when you commute and air-travel.

while there's no such thing as an ASTROPHOTOGRAPHY LAPTOP on the market (yet), here are factors to consider when you plan to use your current one or buy a new one.

SCREEN GLARE : at night this isn't a big issue but when capturing SOLAR IMAGES or setup or shoot during twilight, the reflective glass can make viewing the screen very problematic.

BACKLIT KEYBOARD : you want one of those.

(WIRELESS TRACKBALL) : a trackball doesn't need a big surface to operate on -- that makes it ideal for small setups. Personally I very much prefer trackball over the small trackpad. A mouse needs lots of clean space to roll on -- a trackball doesn't. You quickly get used to one.

SCREEN RESOLUTION : the netbook 1366x786 isn't a terrible resolution but when you juggle several tools, it isn't enough. Images get shrunk a lot. Nowadays, 1080p or better is more or less standard in mid-range laptops. 13" may be sufficient but 1920 pixel width on that screen means some fonts are harder to read. I'd go for a 1920x1200 or better. The extra height is useful to keep the taskbar in view.

PROCESSOR PERFORMANCE : If you pick that laptop solely for the purpose of controlling your astro-equipment, a low-performance CPU with long battery life is your best choice. And there aren't many computing intensive AND time-critical tasks. AstroTortilla can demand CPU power but after the first round, it usually finishes within < 40 seconds on my laptop (using only 1 core of the i5). PHD and other tasks don't need much computing power either. NEF/CR2/RAW/FITS image preview does benefit from faster CPUs but you're not doing image editing in the dark, are you ?

Hard-disc or SSD : My answer is BOTH. buy the laptop WITH HD. That HD has the recovery portion of the OS and is the only way you can proof your software is legitamate. Clone the HD onto a (smaller, cheap) SSD and keep the HD is a safe place. The SSD is tougher when it comes to travel and bumpy handling.

USB ports : you never can have to many of those but to be practical consider this : 1 x USB3 to store images, 1 x wireless KBD/Mouse, N x astro-accessories. Hooking up all the equipment directly to the laptop isn't practical and creat mess of cables ==> use 1..2 cables plus 1..2 USB-hubs.

external video output : HDMI is my No. 1 priority (I've made the switch away from VGA) but yes, you find VGA in many conference rooms ==> VGA is a plus.

Tethered Gigabit-Ethernet : a must. to me. WIFI is nice but not as fast as 1G ethernet and more hassle to secure.

~~CD/DVD writer~~ : In an astronomy laptop this truely is obsolete unless you want to watch "CONTACT" on a DVD while gazing at the stars. For other use, I still want a optical drive with a tray -- numerous driver software came on tiny CDs and I have bootable rescue CDs. You can use a USB-CD for that most of the time -- but not always.

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2" mirror diagonal to attach various eye-pieces -- likely you already got one with the purchase of your telescope. Purists will recommend more expensive options but this is good enough to get you going. Even as a photographer, you don't want to skip the VISUAL observation opportunity. Not only is it amazing to have a 1st-hand view of the sky without the interference of a camera, Polar-, GOTO- & Drift-alignment can be done without a camera. Visual observation with eye-pieces of different magnification is very useful and provide views, your camera cannot capture.

From my (limited) experience with Eyepiece I suggest these -- magnification is based on the telescope's focal length, apparent FOV is related to each EP.

-) Orion 35mm 2" wide-angle EP ($80) with large FOV isn't useful for alignment but excellent for observation -- even with the big reflector, the FOV is nice.

-) Orion 20mm 1.25" Illuminated Centering EP ($100). While it is only 1.25", I like the FOV and eye-relieve, crosshair for precise drift alignment & GOTO calibration.

-) some reviews also suggest the 12.5mm Ploessl ($80) -- much narrower FOV and larger magnification make this EP an option for more accurate approach.

-) different eye-pieces require different focus position, some vary by 2 inches !! ==> there are ZOOM-EP and IMO the major benefit is the ability to zoom with no or very little refocus (and no need to swap EP and extension tubes). These EP are more expensive -- in the $300 range for a 8...24mm with a decent wide FOV. You decide if this convenience is worth the extra $$$ --- BTW, some non-zoom EP cost the same or more .... Orion offers a $80 zoom but the apparent FOV is much smaller

-) I have several BAADER EYEPIECES, including the 8-24mm zoom-EP ($300). Convenience is one factor and the FOV is good. Baader eye-pieces also have one unique advantage : with a simple adapter ring, you can connect your SLR to it : /stargazer95050/19378985

Before any purchase, you should use CCDCALC or STELLARIUM's Occular view to try out the different telescope + EP combinations: /search/photo?w=315163&q=pageant

A pocket full of tools can safe your night as you frequently have to make all kinds of adjustments to the mount and other parts : /stargazer95050/30487429

COMPASS : for Polar Alignment

BUBBLE LEVEL / (digital) ANGLE METER : for Polar Alignment

GPS : optional, for Polar Alignment

(digital) Caliper : measure position of focus

(black) tape & pens : mark zero- & leveled-position, tape is removable

Velcro, bungee cords & cable-straps : easy ways to organize the cables

SOFTWARE-tools -- that's a whole different can of worms

USB-to-RS232 adapter for the EQ-mount : I find it very useful to connect the mount to the laptop. And since I am using that laptop to control the camera (and for autoguiding) there's no reason not to connect it. The handcontroller knows a lot of targets but combining camera + mount, even without auto-guiding has very unique advantages : improve pointing accuracy : /stargazer95050/636937 and "click & slew"-approach. From star-map to actual stars : /stargazer95050/636653

USB-hub & camera-cables : Initially you may shy away from the extra effort and you can continue to use the camera's interval timer or cable release. Reviewing results on a larger (laptop)-screen at comfortable angle is just one of several benefits a laptop adds. You can run more flexible exposure-sequences without constantly adjusting settings on the camera or remote.

Auto-guiding setup + laptop : this will be a (future) step forward to perfect imaging. The requirements for the laptop aren't very high and much of the software is free or low-cost : /stargazer95050/636653 & /stargazer95050/636937

Adding auto-guiding is a bigger step -- a more expensive one. Personally I see more advantages in using a separate guide-scope and I explain why here : /stargazer95050/637119

Big tent & sunshade : it may sound absurd to suggest to an astronomer to buy a big sunshade -- but it isn't. To prepare for a shoot, you have to be out before sunset, or even stay on location for more than one day. You also want to keep (big) telescopes out of the heat. A 10x10ft shade can protect you & your equipment. To increase the shade, I suggest to add some Aluminet to close of the sides too ==> my setup : /stargazer95050/33230517 if you go for extended stays, this is very helpful : $75 ..$100 for the tent. Covering your RV, camper or tent, also helps to keep them cool $50...$200 for the Aluminet.

If you like solar observations (or solar eclipses), you will agree a sun shade is useful. And this being a tent, it also provides coverage from the other enemy -- mist & dew.

All in all summarizing the expenses -- you'll have to add taxes based on you local & shop. For your orientation, I've listed the S&H for big or heavy items. YMMV.

The ZEQ25 : $850 + $35 S&H -- consider additional counter weights ($100)
triplet (700mm f/7) refractor : $1500 + $35 S&H, fell free to spend more or less
12V battery + charger for mobile use $30...$50, more for Li-Ion
optional : D-style Losmandy rail 14" : $70 + $10 S&H
Finderscope : $200 for a good one with solid rings (or $100+ $60 + DIY)
2" to SLR adapter varies from $20 T-ring to $60 for combined T-ring + 2" nose-piece
set of 2" (diameter) extension tubes : maybe you won't need it in the beginning. Later, I found out I did. I think I paid $90 for a 3 piece set.
2" mirror diagonal -- $0, included with my scope
I recommend to add two GOOD eye-pieces -- your choice. each $50...$100, the zoom eye-pieces are a "luxury item" and cost $300. I DISLIKE the tiny eye-pieces that often are included or those 5 for $99 bundles.
box of mechanical tools : the big ticket items on that list are the compas ($25), digital caliper ($25) and digital bubble level ($25...$40). Add some Allen-keys, wrench and other accessories, $100...$150 will give you plenty of useful tools
USB accessories : The hub is < $10, the RS232 varies but IMO shouldn't cost more than $30, add a USB extension or RS232-cable to bridge the gap between mount & laptop. ==> $50 should be sufficient
The tent accessories -- initially $0. Later you may see the benefit of having extra shade and spend < $200

Earlier, I suggested, you put the expenses in relation to existing Canon or Nikon SLR equipment. A popular lens, and moderately expensive one, is the SLR's 70-200VR @ ~ $2400. Tripod + (ball)-head + L-bracket can range from $200 ... $2000. Without a camera, your investment easily reaches $3000 for a good quality setup.

The telescope basics add up to ~$2850 (no extra eye-pieces) and that sum includes a tripod, a mount & 700mm triplet-telescope plus accessories. You sure are getting a lot more for your money. And if you happen to have a 70-200VR, you are welcome to use it on a motorized telescope mount ($20 for an adapter rail to fit the camera onto the telescope mount).

25lbs of equipment already is a considerable size -- but you reach that limit much faster than you may think -- especially after you add auto-guiding equipment to improve your astrophotography results. Example /stargazer95050/28508957 To improve guiding accuracy, you don't want to max out the load. Therefore, if you want to have more margin for future upgrade, start with a mount capable of handling a heavier setup. Usage will be no different -- price & weight are. My choice was the iEQ45. That is about $1000 more expensive than the ZEQ25. If you feel like it, there's no upper limit : astro-physics-1100-german-eq-mount

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© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print

What setup do you suggest, I should buy for Astro-Photography? #1, the Mount

nobody@ipernity.com (Stargazer95050) — Wed, 25 Mar 2015 06:34:16 +0000

Stargazer95050 has posted an article:

Many serious photographers are fascinated by the night sky and given their existing investment it makes good sense to look for ways to re-use some of that. And IMO buying a good motorized EQ-mount, it is a good stepping stone -- and I am not a fan of these simple star-tracking devices. Read "So you want to be a Stargazer -- steps I would avoid & steps I suggest"

Now what would be a "good motorized EQ-mount" to start with

If you are sure you want to follow this hobby for more than just a few weeks, my suggestion is to start with a mount in the $700...$999 class and I explain to you why. If you haven't read it already, I recommend this article www.bythom.com/support.htm about tripods. And the same lessons apply here -- you save money in the long run because you skip some upgrade steps. Furthermore, with a GOTO-telescope mount, the added precision & (electronic) features makes it easier to learn, setup & use the mount and get your lens pointed at the intended target. This can cut the learning curve and save you time and frustration.

Here's a list of features, a good starter mount must have & some, it should have

for astrophotography, buy a motorized EQ-mount with "GOTO"
mount & legs must be sturdy and in the beginning 25lbs load capacity may look a lot but within a year or two, your upgrades may approach that limit.
be sure the mount includes a USB or RS232 interface & ASCOM-driver -- after a few months or a year, you will see the benefit of attaching a laptop to your mount & camera(s)
if available, pick a "dual"-saddle that supports (smaller) Vixen as well as (wider) Losmandy rails. That saves cost & weight and adds flexibility -- dual-saddle has nothing to do with attaching two individual saddles. Attaching two separate saddles/scopes is possible with some mounts and it can be useful in ALT-/ AZ-mode.
ST-4 guide-port is standard for most mounts
Look at the different mounts and their weight -- some innovations mean, even a lighter mount can perform as good as much heavier ones. When traveling, the size & weight can be an important factors.
a built-in & adjustable polar-scope with an illuminated reticle can be helpful
The number of objects in their database IMO is meaningless 5.000 or 50.000 isn't an important criteria -- if you need that amount of detail, you will use autoguiding with an attached PC and get bigger, more up-to-date databases for free,

There are some features & advantages that are harder to spot and you may have to dig into the (online) user's manual beforehand

built-in GPS can help with polar alignment by providing accurate time & location. Spending an extra $100...$150 on GPS is IMO too much. A built-in GPS at no extra cost is nice. You use GPS ONLY ONCE at the beginning of each setup -- so don't overestimate the usefulness of built-in GPS. Your phone likely provides the GPS-information and you quickly can type the coordinates into the hand-controller.

Even with GPS built-in, not all hand-controllers can set time, timezone & daylight saving time correctly -- I mean you, iOptron.
Some telescope hand-controllers show only few information (2 line text) other vendors have controllers with 4...8 line (graphic) display. I prefer the those.
"Balance Test" is a feature I have come to appreciate because it places both axis in a supposedly horizontal position. This is simplifying polar alignment as you can make adjustments before letting the mount slew back to its zero position. So far, only iOptron has that feature but you may be able to emulate that with a few tricks.

PS : iOptron does place it in horizontal position, the actual balancing feature to determine balance wasn't so successful. The old-fashion way did win every time.

If you are certain, you don't want to use heavier lenses, there is a $400...$500 option. The SmartEQ has many features I recommend. Combining the polar scope (included with the PRO) with the GOTO-alignment procedure helps to finish that task more easily & faster. Hand-controller to slew to targets make navigation easier. The max capacity of 5kg limits the growth potential. IMO, it outperforms the various "tracker" devices while it costs less. Great for your dSLR + medium-tele -- if you have plans to buy a telescope, save the money and read on. Additional arguments against the star trackers: /blog/stargazer95050/657809

The iOptron ZEQ25 is IMO a very good match for an Astronomy-Enthusiast's first mount and with a max load of 27lbs (12kg) it is capable to hold a good-sized refractor, guide-scope, finder-scope plus camera. The weight of the mount is lower than many others -- a welcome feature if you travel.

Celestron has discontinued its popular CG-5(GT) and now offer the Celestron VX -- the head itself is heavier than the ZEQ25 (17 vs 11lbs), slightly larger load capacity (30 vs 27lbs) and a similar base price ($800 for both). The ZEQ25's odd shape means the gears to drive the axis are larger and potentially more accurate & more torque than those inside the VX. Maintenance is easier too.

Other factors to help you decide which mount you want to buy

are there active groups on Yahoo, CloudyNights, Flickr, your astronomy club ==> they can give you first-hand advice
read the online User's Manual and study the options how to perform polar alignment ==> that is a step you need to do often and the easier it is for you to follow these steps, the better.
when you google for "hyper-tuning ZEQ25" "hyper-tuning Celestron VX", what do you see ? ==> Like car enthusiasts, owners often aren't satisfied with the stock delivery and tweak it. This kind of search will show if problems are big and if there are solutions. Some of those are DIY and can be done with very few tools. Others are major heart-surgery operations
availability & price of accessories (add S&H) -- with all mounts, I inevitable needed at least one extra counter weight. shaft extension, semi-pier ==> You may not need any of those but it gives you an impression which mount is popular with enthusiasts.
dual-saddle to attach VIXEN & LOSMANDY-style rails is a very welcome option -- upgrades or adapters can be expensive ( $150 or more). the ZEQ25 and mounts with lower capacity often only supports Vixen. Losmandy is superior with very heavy scopes.

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If you want to start with a more powerful mount, you can do that too -- the principles are the same whether it is a $20.000 or a $1.000 mount. The 20k mount usually is a lot heavier and hopefully precision is better. Given recent technological improvements and increase in supply, you may not need to spend $20.000. There are capable mounts in the $2.000....$5.000 range. But just like with sports cars, a BMW M may not be as attractive as a Lamborghini. OTOH, a sporty Toyota is the most suitable option for most -- same with telescope mounts.

To make the most out of these expensive & high precision mounts, you also need a rock-solid, stable setup and better have performed a high precision polar alignment.

Unless you have a backyard with a stable shed and good seeing condition, spending tons of money on a telescope mount is not helping much -- to make the best of such a mount you need time to set it up PRECISELY and that effort only pays off if you don't have to repeat it every night.

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The following list is sorted by price from top to bottom -- I've skipped the very expensive options but if you want, Astro-Physics will sell you an off-the-shelf portable mount head, (54lbs weight, 110lbs capacity) for $16.000. No legs or pier. The $5000 EQ-8 includes a nice pier and also claims 110lbs capacity. Over-kill for a "portable" setup.

Skywatcher EQ8 (Orion HDX110) : www.flickr.com/photos/gharbob/9546630247

It is a monster and you better have an observatory or at least a shed for it -- not something to take on a roadtrip. Pieces still are portable : watch?v=hznsz5qyz4A & watch?v=RCD0XUT5m50 & watch?v=syp9HUWzGNE

This "monster" has one rare feature and that are fixed incremental encoders on each axis -- Orion calls the "Closed-loop GoTo electronics". Other "pro" mounts with a $10k price tag charge an extra $2000...$5000 just for that option -- Orion sells this mount incl pier for $5000 -- IMO a good deal -- if you have an observatory and dark skies.

The iOptron CEM60 & CEM60-EC ($2500, the EC with fixed, on-axis incremental encoders is $3900, neither one includes a pier or tripod) also are heavy lifters. 60lbs is a lot (the EQ-8 is rated 110lbs). The head of the CEM60 weighs a moderate 12kg/27lbs, still noticeably less than the CGEM (40lbs) and a lot less than the EQ-8 (not listed, approx 50...60lbs)

The CEM60's firmware IMO isn't yet ready for primetime -- www.flickr.com/photos/astronewb2011 has posted, that only recently did he receive the update to support auto-guiding [JUNE 2014].

The Orion Atlas Pro AZ/EQ-6 also offers (fixed on-axis incremental) encoders (titled "closed-loop electronics"). If it weren't for those, the $2000 (incl 2" tripod) would appear expensive given the 44lbs capacity rating. This mount also has another nifty feature -- you can tilt it to use it as a Alt/Az mount without much disassembly. For visual or terrestrial observation, this can come in handy but you pay for this, with some extra weight. This mount, like the Celestrons, put the gears & electronics on the inside of the metal case ==> well protected but the radius of the gear is smaller decreasing accuracy.

iOptron and many other manufacturers place the gear on the outside, even increase the diameter to get more teeth and thus improve accuracy. Maintenance also becomes easier with motor & gears on the outside.

The Celestron CGEM series (incl DX & CGE Pro) have some catching up to do. Significantly heavier & more expensive and -- at a similar price -- lacking technological improvements, like the on-axis encoders.

The CGE Pro list price is $5000 but IMO it is a generation behind in terms of accuracy & features when compared to the $5000 EQ-8 mount. Weight is similar or more.

The iOptron iEQ45 is at the bottom of this list, because it is the cheapest ($1800) and only the old CGEM models cost less ($1500). Rated to carry a 45lbs load puts it on par with more expensive mounts. The Atlas Pro also is rated 44lbs and priced $2000 (no GPS) -- a bit more expensive and at 50lbs, nearly twice as heavy.

There are some advantages the iEQ45 has over the CGEM and the Atlas (Pro) :

CGEM & Atlas Pro require you to loosen the central screw which also is responsible for spreading the tripod legs.

With the iEQ45, I can setup, level & tighten the tripod legs with no need to attach the mount's head. Furthermore, during polar alignment, there's no need to tamper with the tripod legs & screws -- the CGEM & Atlas require you to loosen that screw and to do so, you also need to unscrew the leg spreader's screw.
The display of the handcontroller of the iEQ45 is much more informative -- shows Alt/Az plus RA/DEC and more. The 8x20 graphic display is a big improvement over the 2x20 characters. It can show a graphic of the expected position of Polaris in the polar scope ==> small difference but over time, you really appreciate it
the polar scope in the iEQ45 includes an accessory to illuminate the reticle - the CGEM doesn't have this option, not even as an $$ upgrade. Eye relief distance is very small for both scopes.
power & RS232 connect to a fixed point on the iEQ45 -- the CGEM's power plug moves as the mount moves. The CGEM's RS232 cable attaches to the hand-controller, not the mount ==> trip hazard.
It may seem trivial but small detail have a big impact. To better level the base of the tripod : /stargazer95050/29051567 -- the feet of the CGEM don't have such threads :-(

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Coming back to the original question -- STARTER MOUNTS for an enthusiast.

Even if you "only" want to eliminate startrails, you may not recognize a full-featured EQ-mount can do all you want and more - and still cost less than many startrail gadgets and tracker devices. For example, the Skytracker costs $399 (no tripod, no polar scope, no computerized goto, <8lbs payload, 2nd tripod head required). The AstroTracker cost >$600 and requires more $$$ accessory.

Compare that to the SmartEQ Pro mount priced $499. That includes a tripod, has GOTO, has a polar scope, can carry 11lbs, has improved gears, additional tripod head optional / recommended.

While photographers want to re-use their investments, often they fail to recognize lower-cost alternatives and are lured into buying over-priced accessories. More on "tracker" vs EQ-mounts : /stargazer95050/657809

The ZEQ25 mount isn't very heavy and, according to spec & user reviews, can move a decent setup. It features a build-in GPS at no extra costs and the handcontroller has a more informative 4-line display -- better than the Celestron & Orion (they charge $150 to add GPS) and a step below the more expensive iEQ45 (8-line graphic LCD, GPS built-in). And by now, it appears the early issues have been flushed out.

If you want start astrophotography and plan to upgrade soon to a bigger / heavier lens, the ZEQ25 may be too weak, to carry that OTA plus the auto-guiding scope. The iEQ45 is the mount, I currently use and weighing only 20lbs, it is a very portable mount. Compared to the Atlas-EQ6, the iEQ45 weighs much less, is cheaper (GPS included) and has a few more extras (better HC & polar scope). The Atlas-EQ6 on-axis encoders and the ability to tilt it to Alt/Az are useful and make this a tough choice.

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© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print

So you want to -- match a photo and a sky chart

nobody@ipernity.com (Stargazer95050) — Fri, 23 Jan 2015 04:32:06 +0000

Stargazer95050 has posted an article:

As much as I like STELLARIUM, this time, it lacks important features. Instead, I use STARRY NIGHT SE -- that SE edition is bundled "for free" with the purchase of many of Orion's equipment. While this version has been stripped of some features, it still is very useful. If you have a $0 copy, I suggest you give it a try.

Another alternative to Stellarium is CARTES DU CIEL (often abbreviated as CDC). sourceforge.net/projects/skychart -- it has many of the same features as Starry Night, possibly even some more. It costs $0 with no strings attached. The display of the sky is a map -- not the kind of realistic rendering with twilight and atmospheric simulation you see in Stellarium & Starry Nights. This can be an advantage as it uses a lot less CPU power and won't drain a laptop battery so quickly when you run it during a nght of observations.

How does this work

The basic flow is like this

you take a photo of the sky -- if the photo doesn't include EXIF date & timestamp, take a note roughly when it was taken.
a blind plate-solver -- e.g. Astrometry / AstroTortilla -- will determine the coordinates of the center of that image
AstroTortilla sends a command to the ASCOM-driver & the (virtual) telescope
Starry NIGHT or CDC monitors the position of that (virtual) telescope and shows the matching sky chart. (set same date & time as photo)

This looks like a very complex setup -- but in most cases it works seamlessly when you follow the basic / default installation steps

ASCOM DRIVER -- unless you already use a telescope, this isn't a tool you have heard of. You can use this even without a mount and only use the SIMULATOR and the hub. That's the link to connect the Plate-solver & Sky-Chart. You can find the software for free at : download.ascom-standards.org

For this use case you don't need to download anything else -- if you have a telescope mount or cameras, you likely already have all that installed.

PLATE SOLVER -- my favorite solver is ASTROMETRY / ASTROTORTILLA. When you download Astrotortilla via sourceforge.net/projects/astrotortilla/files/latest/download you receive the entire Windows-based package plus the simple GUI interface and it will download the various maps needed to solve your images.

If you are a Linux-user, you can use Astrometry's original code and skip the window's adaptation.

SKY MAP -- currently I use Starry Night SE -- it works good and I have a "free" copy. It also is my tool to send slew commands to my telescope mount. In Cartes du Ciel / CDC you may have to manually use "Track Telescope", in Starry Night there's a checkbox "Follow Scope". Since I started playing more with CDC, I can see additional useful features.

Stellarium lacks the ASCOM interface and even StellariumScope did not provide the missing functionality. StellariumScope can send commands to the mount via ASCOM -- BUT in this setup, the important feature is to RECEIVE & continously MONITOR ASCOM-commands and use those to FOLLOW the telescope's position and show it on the map.

In effect you can use any program you like if it can connect to a ASCOM-compatible telescope. The map doesn't notice the telescope is a simulator.

Below you see a simple flow-chart -- after you've installed the tools

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STEP 1 :

You launch Starry Night SE (or other tool of your choice). Connect to the ASCOM telescope via GENERIC or POTH HUB -- do not connect directly to "Simulator" !!

After choosing "Generic Hub" (or POTH) select "Properties" and there you should pick the "Simulator". The default settings of the telescope simulator good enough but you can select "Properties" to open the window with the options. I switch off the "always on top" option. Also enable "start tracking" option.

After you have connect Starry Night or CDC to that virtual telescope via a hub, you have to enable the option "FOLLOW SCOPE" option -- THAT makes it convenient ! If you forgot, you can enable it later or scroll around until you see the telescope's crosshair on the sky's map. If the mount is not tracking automatically, enable tracking from Starry Night directly or make your way through the ASCOM options.

STEP 2 :

Before you start analyzing your photos, review the EXIF-data to determine the time & date. If you travel frequently & wide distances, lookup where you took the night sky photos. Stop the real-time clock of your sky map and change the date, time & location setting to match your photo's timestamp ==> now the chart matches the sky you saw during the shot -- Especially when you aim at planetary objects, using the correct time is important as these elements are not on fixed positions in the sky. A star's RA- & DEC coordinates are fixed and the solver's position will show you the correct location. If the locaton or real time & observation time differ a lot, your target in the simulation may now be below the horizon, while you were able to see it in real life.

STEP 3 :

Launch ASTROTORTILLA and use the drop-down menu to connect to ASCOM. Since there already is an active ASCOM hub (Step 1), you should pick the same hub and click "OKAY" (you cannot modify the settings of the existing connection),

Be sure to set min- & max FOV to reasonable values and match the diagonal FOV of the lens(es) you've used. Also you may have to adjust "sigma" setting.

RECOMMENDATION : from my experience, I prefer to use "arcminwidth" as a basis to define the FOV -- one degree = 60 arc-minutes. (more later)

STEP 4 :

AstroTortilla has the option "SYNC SCOPE" -- THAT IS IMPORTANT. If you cannot enable SYNC (box is gray), your telescope (simulator) is not tracking and you need to enable that.

STEP 5 :

AstroTortilla has the option to directly connect to cameras or use previously saved images ==> right now, you want to use the latter. While you analyze images you took hours or days ago, you will have to adjust the date & time setting in the sky map program. CAREFUL !! use the EXIF setting "Shooting Date/Time" -- other timestamps may be inaccurate and reflect modification of the file, not the time it was captured.

RECOMMENDATION : All my photos are organized in folders starting with YYMMDD filename -- that narrows down the date. Additional sub-folder for different events or sky locations help to confirm if the Plate-solver's solution is reasonable. By dividing up results you simplify the task of stacking images -- each target of that night has its own sub-folder.

Small difference in time will result in small & acceptable mismatch in the display. Except for objects in the solar system, the coordinates are independent of time & date.

The two options (AstroTortilla's) "SYNC" & "FOLLOW/TRACK" in Starry Night / CDC are the key to make this work conveniently -- AstroTortilla solves the image's position and send the coordinates to the virtual telescope via a "SYNC" command. Starry Night (or CDC) monitor the (virtual) telescope's position and after receiving a SYNC, the position changes ==> with the "FOLLOW" or "TRACK" option enabled, the map will show the new location in the middle of the screen. CDC usually, but not always, will follow the changes in the telescope's position -- if not, you have to use the "Track Telescope" function.

At the moment, this combination of tools only will SYNC the center position of the image you've captured. You still need to manually look up the date and the (approx) time. And for better comparison, you want to have a frame depicting the FOV based on the camera & telescope/lens choices. Neither CDC no Starry Night will annotate the picture like you see in results from the Astrometry flickr group.

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Improving the solver's performance & avoiding mistakes

A few words of caution -- steps you should follow when you want good results fast. There is no magic one-fits-all setting -- but there are some cardinal sins that can make any plate-solver a huge waste of time.

You should heed these commandments :

ACCURATE FOCUS is really, really important. If you have a bright star, your camera's autofocus might be usable. Even if you want to look at other parts of the sky, use that bright star to determine focus. After that, disable AF (clutch or switch on the lens) and preferably use a wrist rubber band to prevent zoom & focus position to change. Especially when pointing up, the weight of the lenses can drag the zoom & focus down.

Blurry, over-sized / out-of-focus stars is one sure way to throw off the solver and have it waste your time waiting for useful results that never come.

ROUND STARS -- You have to find a balance between high ISO and elongated startrails. Too high the ISO and the camera's noise may be mistaken for stars in the sky. Too long an exposure and you have trails and the plate solver cannot identify them as stars. A polar-aligned, motorized tracking mount makes this easier.

SUFFICIENT CONTRAST -- with a motorized mount you can extend the exposure time but that can get you into trouble when you are in or near a city, as the orange glow of light pollution will wash out your exposure. A LPS filter helps (but extends exposure time).

SIGMA -- this parameter in Astrotortilla defines the threshold between real stars & noise. If you set it high, you may not get enough stars to solve the position, too low and you overwhelm to solver and likely include many "fake" stars produced from camera noise.

REASONABLE SETTINGS -- you can download all the maps and define to search the entire sky and let the solver assume the lens' FOV is between 360°...0° -- just don't complain about how long it takes to come up with a solution. With a few minutes of online research you can determine the FOV of your camera + lens (CCDCALC, en.wikipedia.org/wiki/Angle_of_view and other sites & tables).

Starting with "SIGMA = 1" is the default but is asking for trouble. Instead, I'm starting with a much higher threshold and reduce it. Keep an eye on the "number of stars found". That result is briefly displayed in Astrometry's status bar. The official help-page recommends to have ~200 stars, in my experience having 30...60 stars yields higher accuracy and much faster solutions and therefore I start with a high SIGMA value. And if I cannot get a solution, I decrease the value by ~25% and try again. YMMV.

Similar, you will recognize, capturing a 10...30 MPix RAW image and send it to the solver is overkill and a waste of time while a 2MPix JPG image usually is more than enough.

After a few attempts / nights, you will gather s couple of (SIGMA) settings combined with ISO & exposure and those will quickly give to good plate-solver results. You need to experiment a bit on your own. There is no UNIVERSAL SETTING to fit all needs -- and the values I mention are starting points not the ultimate solution.

DO SOME SANITY CHECK -- especially while you're getting started and your flow is untested (and you include many high-res maps) it can happen that Astrometry finds an accurate match -- but it is in the wrong place. In that big wide sky, patterns are not completely unique and therefore Astrometry can make a mistake, especially when the parameters are very vague (wide). The better the settings match the actual setup, the lower the chance of misunderstandings. But in the end, YOU HAVE TO CHECK THE RESULTS -- and using the virtual telescope & sky-map helps.

Often you focus at a bright star to begin with. Or at a well known Messier object -- run the solver and use the virtual telescope mount + CDC show you the results.

I have observed failures of the Plate-Solver -- and usually it was my fault:

- a position was reported as NCP when it should have been UNSOLVED

- at times the "solved" position was way off -- the best way to identify the mismatch was to look at the sky map and compare it to the photo. For example, there was a huge, bright star in the photo and the "solved" position lacked any bright star.

- with a simple diary, you can document the INTENDED targets ==> I'm using APT to capture images and specify the target ==> APT creates sub-directories "YYMMDD" for each shoot plus individual "target" sub-directory trees. These targeted positions will help you check if the solver has gone off the reservation.

- My SUGGESTIOED PRACTICE : setting the min- & max FOV to be +-50% of the assumed diagonal FOV is not a very challenging constraint. Often I use a FOV of 15...900 arc-min (1/4°...15° FOV) to cover all lens + camera combinations and with proper SIGMA values get results in < 30s.

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PC requirements :

The requirements aren't unusually high and naturally it helps to have a faster CPU. Having MORE CPU CORES DOES NOT HELP -- the solver wasn't developed for multi-core. High-end graphic GPUs have no impact. Vast amounts of RAM help a bit but not much -- use it to cache HD the helps. Faster disk helps, especially with large maps & high image magnification.

The volume of maps to solve your images depends on the maximum maginfication of your telescope + camera combo ==> Higher magnification, thus narrower FOV requires more details and that means larger volume.

AstroTortilla itself is tiny but it requires ~300MB "Mini-Linux" environment (Cygwin) to function. And you have to add the sky charts to that ... C:\cygwin\usr\share\astrometry and that volume can range from another ~200MB to over 28GB. For most users, ~1GB is sufficient. Enthusiasts with larger magnification, may require ~3.5GB maps.

For my astronomy & real-time use. I have an old-fashion laptop. 13" netbook LCD and a i5 CPU and it handles the plate-solving very well. A faster CPU helps but often is limited by the HD access to the many map images. Usually I get results from the solver within 30...60s. If it I have no result after waiting > 2 minute, I usually abort & reshoot with new settings (EXCEPTION : very first attempt and shots close to Polaris -- there, I wait ~3 minutes before I pull the trigger and abort). see uncut video in real-time : www.ipernity.com/doc/stargazer95050/28668501

If you don't define a deadline and your setup or parameters are bad, you can waste 30 minutes or more and AstroTortilla still won't come up with a result. (Yes, when I started, I did let it run that long out of curiosity ...)

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© Copyright 2015, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print.

So you want to -- build your own, "chic" NAS server

nobody@ipernity.com (Stargazer95050) — Wed, 24 Dec 2014 19:34:09 +0000

Stargazer95050 has posted an article:

You are sure you want a NAS server and don't settle for a simpler, cheaper alternative. You've read /blog/stargazer95050/808620 ?

Okay, so you are ready and willing. The NAS-server I plan to build has very specific requirements. In IT jargon, these servers are often referred to a "COLD-STORAGE". The incarnation of a backup system. You write to it occasionally, and you much more frequently read than write. It can be hours or days between accesses. I prefer to call it my MEDIA JUKEBOX instead of cold-storage but the requirements are very similar. If you are planning on streaming four or five 4k-HD movies at the same time, you will first need to update your network before you worry about the NAS server's performance : 1080p needs 12...19Mbps, 4k Bluray delivers at least 50Mbit/s. The bitrates you see in the WIFI commercials are best-case scenarios and streaming a single 4k Bluray over WIFI already can be a challenge for many WIFI receivers -- if in doubt use CAT5 cable & gigabit ethernet

My priorities

-) Favor huge storage volume in compact size (and low noise and low power)

-) Low access times and sustainable speed to stream 1...2 1080p videos is important, there rarely is a task requiring frequent & fast file accesses (no need for indexing ...)

What can be equally important are power-management features

-) unused HDs should go to sleep / stop spinning whenever possible

-) CPU should be a low-power, passively cooled version

-) hopefully the fans in the case are off most of the time

Selecting the "best" case for the job, I decided the Silverstone DS380 is the one (read more /stargazer95050/36361168 ). 8 x 3.5" bays, easy to swap (plus another embedded 4 x 2.5") make this the case with the most Terabyte per cubic-inch.

Since this is an embedded server, the PCIe slot will not host a power-hungry graphic card

You need an additional 300W...450W SFX power-supply. A rough estimate of 12 x 25W for the HD plus 100W for MoBo & CPU means a 450W is more than sufficient. IMO, that calculation is overly pessimistic. For a system like this CPU & MOBO should consume < 60W (peak) and assume 4HD at typ power and 8 HD in standby or even sleep (total < 120W for HD) , means even a 300W P/S has ample of margin. HOWERVER !! -- when choosing a low-power supply the software and hardware must make sure NOT TO POWER ON ALL DRIVES AT THE SAME TIME !!

For this application, a low-power CPU & MOBO should be sufficient and those don't need bulky coolers.Some use passive heatsinks - pick those, if possible.

Now comes the first choice -- what CPU & MOBO combo do you pick ? -- These are suggestions and you can pick whatever you like. Given the DS380 mechanical constraints, only Mini-ITX boards qualify. Alternatives : /stargazer95050/36361168

Here are some of the candidates I have lined up -- especially with large capacity and good looks (living room) in mind.

If I would plan on putting that server into a closet or an enterprise environment, the choice would be easy -- either recycle a used ATX tower or a non-descript 19" rack unit. Since this will reside in my office or living-room for easy access to the drives, the look also is important. Smaller size (no huge ATX tower) also is a requirement. For this task, I really like the Silverstone DS380

The radest solution -- one which may go well above the home-user setup -- would use a motherboard with multiple SAS (instead of SATA) ports and provide you with the option to add more external SAS storage

A) ASUS Mini ITX board with C2550 CPU & 4 x MiniSAS could connect up to 16 SAS/SATA drives. Plus an additional 2 x SATA-only ports. Like similar boards, this doesn't include a fancy graphic card and even the PCIe slot is only a x8 wide instead of the x16. You're looking in vain for USB3 headers. On the upside, you get 4 x Gigabit Ethernet jacks which can be important to stream 4 x 4K-Bluerays concurrently to different parts of your house.

This MoBo may be too specialized for my use and if I'd pick it, I would add a 4-port USB3 PCIe card. 2 external connectors and an internal 19-pin Molex connector. also I'd add a bracket with 2 x SFF-8087 to SFF-8088 adapters. Those two SAS connections I would use for future expansion beyond the 8 HDs inside this box.

This isn't a cheap system -- in all approx $460. (quad-core) MoBo (CPU is included), 2 x $30 for the add-ons, SAS-cables also add more costs. (still need to add DDR3 RAM. case, P/S and drives. Plus the OS -- I exclude those in the comparison, as they are the same for all systems I describe)

To EXPAND option A), you could add another 8 x HDs utilizing the 2 x ext MiniSAS connectors. and build a 2nd case -- MINUS the CPU-board -- and fill it with discs. Stylish -- YES. Expensive -- NOT REALLY. Off-the shelf 8-bay SAS enclosures start ~ $450...$530. 19" rack solutions cost more. In contrast : $150 for the DS380 chassis, $60 for a 300W power supply, $40 for the internal SAS cables & brackets.

B) Intel + ASrock have build a chip & MoBo nearly custom tailored for this job : The C2750D4I / C2550D4I have 8/4 cores, 12 SATA ports and the CPU uses 20W/14W. Naturally no (2D/3D) graphic engine and video is limited to a VGA connector.

That system LACKS USB3 and since there IMO is no additional need for any PCIe peripherals, I would add a 4-port USB3 PCIe card. 2 external connectors and an internal 19-pin Molex connector.

For a server system, this CPU + MOBO + USB3 combo is "cheap" : ~$400 for the octa-core system, $300 for the quad-core. Adding more discs to this system isn't as easy as with the SAS-motherboard but with a USB3 connection, you have a fast link to add a few more drives.

In the roam of enterprise server motherboards you often have to pay a lot more -- and usually you have to add even more expensive processors. The above MoBo has server features and if you don't need 12 drives and ECC-DRAM modules, there are other less-expensive options using "consumer-grade" boards :

C) ASrock sells different FM2+ boards with USB3 and 6 x SATA-III. The built-in graphic is quite powerful and there even is a decent Audio-IO. When you combine this board with a AMD-A6 or even a A8 Kevari, you have a NAS-server with very strong graphic / HTPC muscle. Once you add a PCIe card with with additional SATA ports, this system outperforms the C2550DI at lower cost. Power-consumption & cooling will require more effort : 65W CPU, 8W Mobo. Even if you throttle the CPU down to 45W, that's twice as much as the C2550DI4, making silent / passive cooling all the more difficult. To boost the number of SATA ports, add a PCIe card (~$60 for 6 SATA channels)

Cost comparison : $80 for FM2A78M Mobo, $70 for a CPU (slower A6 Kevari), add $30 for CPU cooling fan & $60 for additional PCIe-SATA ==> $240 but no option to add extra graphic. The built-in graphic of the FM2A78M + A6K is way superior to anything the C2550 has to offer. If you choose a SAS instead of a SATA card, you can expand HDDs more easily -- unfortunately I haven't seen affordable cards.

Not a real NAS-server, this is a half-breed, a HTPC with tons of storage (possibly shared via SAMBA).

D) HTPC / high-end AMD : It is diffcult to find INTEL boards with all these peripherals while I have seen several AMD chipsets to fit my needs for numerous USB3 + 6 or more SATA-III. The A88X chipset plus Kevari A10 CPU can boost the performance of the system I've outlined under section C). IMO this additional power/heat (95W CPU) is problematic or at least noisy in such a small case.

Opting for for graphic power over more storage, you can add a PCIe-x16 graphic card -- the case has room for that.

While I'd like to have a compact HTPC power-server, the DS380 case lacks the optical CD/DVD drive I require for my HTPC systems. Compared to other mini-ITX chassis, this one allows for quick swap of HD and you may be able to swap a HD tray for a 3.5" expansion / card-reader. The other two cases are bigger on the outside but also are designed for mini-ITX boards with a double-wide PCIe slot. These two cases have the DVD slot I want, but in return, swapping HDs requires more work and total capacity is less -- especially if you add a graphic card.

With the BitFenix case you can choose either Mini-ITX or Micro-ATX form-factor -- the latter naturally is beneficial if you want custom graphic _AND_ sound. And of course there always is the option to use a regular mid-sized ATX tower

This still is a plan. A work in progress but I lean towards OPTION C) and OPTION A).

With A) I get the expansion to 16 easily swappable drives in an attractive & compact combo at a low price (compared to other 16-bay solutions).

With C) I have a good performing HTPC with at least 6 swappable drives and up to 12 drives total. Lacking a built-in DVD-drive is the biggest complaint I have, while others will point to low 3D gaming performance.

PS : I'm not the first to come across this NAS case.

www.techspot.com/review/826-silverstone-ds380-nas/page7.html

b3n.org/nas-server-build-asrock-c2750d4i-silverstone-ds380

$150 for the case, $60 for the P/S, $80 for 8GB memory = $290 plus the cost of the MoBo combo. With option C) that $240, Option B) ~$300 and Option A) about $460.

Pre-built diskless systems with 8 x 3.5" bays cost from $800...$2800. The expensive one sport a powerful Xeon E3-1200 v3 3.4GHz Processor

And you can skip the DIY part and buy a 4-bay chassis like this for $300 : www.zdnet.com/pictures/best-nas-drives-for-work-and-play/6 The feedback is scary -- and it is not just one or two : www.amazon.com/Cloud-EX4-Diskless-High-performance-reliability/product-reviews/B00G4JZ2T0

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© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print.

So you want to -- get a better shot of the Sun

nobody@ipernity.com (Stargazer95050) — Sat, 01 Nov 2014 05:14:20 +0000

Stargazer95050 has posted an article:

Hydrogen-Alpha, or short H-alpha, observations are popular ways to see more details of the sun's surface & corona (and are kind of affordable).

With the same approach but different or tunable filters, you can further refine observations and possibly overlay different measurements -- but there you enter the VERY EXPENSIVE territory (Daystarfilters & Luntsolarsystems). Sometimes the different filter- / wavelength images are stacked & colored.

Using a narrow-band filter isn't the only secret to improving solar images. These details will be blurry or even invisible when you watch them through a turbulent atmosphere and don't apply corrections / post-processing. Therefore an additional strategy is to capture lots of images using an uncompressed VIDEO-stream instead of a single still-image. Given the brightness of the sun (even with ERF- or H-alpha filters) shooting at < 1/60s or even 1/100s is very feasible ==> 15...100 frame per second streams are possible. Compared to one shot every few seconds with a SLR (#1)(#2)(#3)(#4).

One opponent to getting sharper images of our planetary neighbors and the Sun is the Earth's atmosphere. Not only does it (unevenly) absorb light's different frequencies, it causes diffraction, and it also is unstable and dynamically distorts observations. On a hot summer's day it is worse compared to a clear cold winter night. Different layers of air (e.g. jetstream) cause additional turbulences in the observation.

It is possible to reduce the impact of these disturbances :

-) short exposure times reduce the motion blur

-) trade-off between short exposure (less motion blur) and more noise (higher ISO)

-) shoot many images and use math to reduce noise and improve details

-) better use a mount capable of tracking the target -- preferably an EQ-mount as the target won't rotate during the observation

This approach isn't proprietary to NASA -- you may have seen some lunar images I took and post-processed with the same technology : /stargazer95050/28740045

The first investment for this type of imaging is the "right" camera -- and it is the opposite of a dSLR -- their flip mirrors cause vibrations and the max FPS and depth of the buffer limit the usability. Suitable (video)-cameras usually are controlled solely via USB + laptop and have no user-interface buttons on the outside. They record uncompressed (AVI) streams. You don't want the MPG compression to throw out faint or tiny details, eliminate stars or reduce dynamic range just because the MPG algorithm classifies that as expendable or noise.

Many of these cameras are monochrome -- when you shoot narrow-band images, there's no point in using RGB. In fact, shooting RGB reduces resolution as 3 out of 4 pixels may be of the wrong color.

UPDATE : The doppler-effect causes a change in the light's frequency -- speed & direction determine the shift. With a color camera & high-resolution CCD, it is possible to measure & display that using a single exposure. OTOH, filters can be tuned and you can use a monochrome camera -- but need to record extra exposures for different filter settings. For solar images, AFAIK are less timing-critical and you can shoot a sequence, alter the filter and shoot the next

What's needed

telescope, preferably on a motorized EQ-mount
FAST streaming camera (some use analog video cams + digitizer (video grabbers), others USB-based cameras), preferably with high dynamic range
laptop with USB connection to the camera plus a lot of free disk space -- the uncompressed AVI stream can occupy as much as 1GB/minute !! even on a small 1MPixel image
tool to control the camera and run timelapse and interval shots
post-processing video-tool(s) to perform a number of tasks, including preview, trim, crop, resize and resample & convert to other formats
astronomy-specific tasks : image-alignment & -stacking, various enhancement algorithms, color & B&W
H-alpha and other narrow-band filters aren't a requirement but they benefit a lot from this approach
Beautify the images using your existing photo tools
Combine the multiple stills into a video timelapse

#1 -- if you read this, it is likely, you already own one

#2 -- (approx 2 years ago) I've picked a DMK-41. In 2014, you may find better cameras -- especially USB3 opens the door to higher resolution & frame-rates but make sure your laptop + HD is fast enough. I haven't seen a need to upgrade, but the DMK-23 is tempting but pricey.

#3 -- is something you likely already own

#4 -- often is included with the camera. I disliked that tool and prefer different freeware tool : SHARPCAP. There are others.

#5 -- a small toolchest of open-source tools + codecs can do all the necessary tasks : VirtualDubMod, Handbrake & TEncoder. Add VLC-player for playback & trim of various formats.

#6 -- AVISTACK2 does a great job when it comes to post-processing these video-streams, be it lunar or solar / H-alpha. AUTOSTAKKERT has been recommended in various blogs and seems to have similar capabilities as AVISTACK and also shows solar image processing abilities.

DEEPSKYSTACKER is NOT SUITABLE for planetary images. REGISTAX may do it but I had no luck. IMO, their focus is on starry deep-sky images

#7 ===> I'll discuss that in the next section

#8 -- use your existing tools to improve TIFF & JPG. For simple tasks IRFANVIEW & FASTSTONE provide many useful features and can apply them across a large batch of images

#9 -- many of the tools listed under #5. Or simply use StarTrails (static stacking) or PhotoLapse (output movie)

The technique isn't unique to solar imaging and in fact I first used it to refine images of the moon and with the exception of #7 solar filter the process is the same. Below you see the result of steps 1)....6) + 8) : /stargazer95050/19370405

For MOON images, it ALSO HELPS TO USE FILTERS -- not the extreme narrow ones used for solar capture. Since the moon is nearly B&W, you can use a single color filter and reduce lens imperfections (aberrations, focus-shift, ...)

H-alpha and other narrow-band filters for solar imaging

The FIRST STAGE of all solar observations is a way to prevent the MASSIVE amount of energy from entering your scope and hit the sensitive sensor (be it eyes or camera). Sophisticated solar observatories and casual eclipse watchers need them -- the effort, precision & cost differs.

When you first try to look at the sun you likely will start will start with the "eclipse shades". And as you start to photograph the sun directly, you will have upgraded to one of several forms of (white) Energy Reduction Filter (ERF). Some really show the sun as a white circle.

Other filters are more selective and favor various colors. The setup that took this shot is similar to this and uses a GLASS filter : www.ipernity.com/doc/stargazer95050/19370235. While I like the resulting color, the (rear) GLASS surface causes a serious problem. Light entering the lens hits the sensor but some portion is reflected back and usually that's no big issue. No one notices a small amount of light bounce back out of the front of the lens -- UNLESS. You add a GLASS filter with the REAR of the filter also reflective. This creates filter glare & ghost reflections at an unprecedented scale.

The only cure to that problem I know is the use of shims or other means to angle the filter and divert these reflections out of sight. The MYLAR/FILM filters don't have this problem and next time I likely will pick one of those (and us editing to tweak the color)

The SECOND STAGE is the actual narrow-band filter. This can be a H-alpha Etalon or way more sophisticated tunable filters. Many H-alpha filters combine the energy reduction & Etalon into a single unit or even a custom telescope (e.g. Coronado ). Other filters still require a reliable ERF reduction (not included in their $$$$ price tag).

The THIRD STAGE, especially with H-alpha Etalons, is a bandpass filter -- often located inside the rear-diagonal. The 2nd-stage filters are narrow, but they let pass the upper harmonics (which still would be powerful enough to do harm to the eyes and distort scientific observations) and this 3rd-stage bandpass eliminates these harmonics. Important for astrophotographers is to pick a diagonal & BF (Bandpass-Filter) with the suitable size. A dSLR (1.5x crop factor) with diagonal of "only" 30mm IMO isn't the best choice for many solar H-alpha filters as most of those are using 1.25" tubes and will cause vignetting. I only have looked at the prices for Coronado BF -- and they become very expensive and hard to come by in sizes exceeding 15mm.

Optional FOURTH STAGE is for observers who wish to further narrow down the bandwidth to see more details. I mention this as 4th stage because it isn't for starters and you may want to add it later on. This "stage" is an add-on to Stage #2 -- basically you combine 2 identical or slightly offset filters to narrow the window of light to let pass through. (It doesn't eliminate the need for Stage #3 / Bandpass Filter)

WHICH TELESCOPE ?

That decision is a complex one for a number of reasons -- trying to re-use an existing telescope may be more expensive than buying a dedicated solar-scope and here are some example to consider

Do you have a camera capable of capturing high frame rates with a 30mm sensor diagonal ==> look for a system with a 2" wide optical train (including the bandpass filter).

==> you can reuse your refractor but the cost to add the filters will be very significant. In return, the resolution will be superior. At a steep price.
A "budget" solution is an all-in-one combo like the Coronado 60 + BF15. The optical path is not wide enough for DX-dSLRs but sufficient for many of the smaller & faster CCD imagers, like the DMK-41.

As you contemplate telescope & CCD you should ignore the focal length and instead look at the image of the sun projected onto the sensor (of your fast streaming camera). Yes, a larger aperture means (theoretically) higher resolution -- but when your magnification is high, you cannot capture the the full disc of the sun -- do you want to give up that option ? Furthermore, you want to have some margin around the sun to overexpose an image and capture the protuberances

And before you complain about the prices of these telescopes, please look at the price tags of a simple zoom for your SLR. And look at the price of a high-end lens. A telescope is a high-end lens -- don't expect the $99 telescope in the toy-isle to match the quality of your $999 zoom. The telescope delivers much higher magnifications and it is not a surprise these scopes aren't cheap -- they are far less expensive than a 400mm f/4 Nikkor -- and way cheaper than the f/2.8 or 600mm or longer !!

Here are the reasons why I bought the Coronado 60 (400mm f/6.6) + BF15 + DMK-41

the resulting FOV of that combo is a good match and captures the sun's full circle + room for protuberances : 960 pixel height of the image won't impress SLR-shooters but it is way higher than many TVs and even 720p films. It is close to the HDTV 1080p's vertical resolution.
The DMK-41 delivers 15FPS uncompressed AVI -- I already own this and that setup was proven ==> no extra costs for HW & SW
CAUTION : often you see (cheaper) combos with 5 or 10mm bandpass filter -- the 10mm may be very suitable for VISUAL observation. Imaging requires larger image circle to avoid vignetting.
I have considered the larger Coronado 90mm and decided against it

- it needs a larger sensor to capture full circle images of the sun -- for me, FULL CIRCLE was a must

- naturally it also would require a larger BF filter -- and those aren't cheap
LUNT also makes good solar scopes -- price, availability swayed me towards the "small" Coronado. Plus I have seen results with similar setups and liked them
possible expansion plans using the "small" Coronado 60 setup while staying way below a 90mm Coronado or other options :

- adding a BARLOW to increase magnification --> $150...$800 for FFC

- adding a secondary Etalon to further narrow bandwidth --> ~ $900

- replacing the camera with a new one --> ~ $1000 for a DMK-23

I can mix & match them as I want and gradually upgrade
compare that to the $6000 price for a Coronado 90 (no secondary Etalon, no camera ) : www.optcorp.com/coronado-solarmax-ii-90-bf15.html. Or compare to the $9000....$3000 for daystar filter alone (add camera + scope) : search/result/index/q=daystar

As mentioned in the introduction, solar imaging with narrow-band filters is a very specialized challenge and it requires investments. And as usual, there is not much of an upper limit but the lower entry-point is IMO a 60mm Coronado with BF + camera. You also can use a LUNT-scope.

Or you can use your current telescope and go a DIY route by adding a ERF filter, find a suitable adapter to fit your scope, add Etalon & bandpass and fit that into your optical path. And add a (fast, monochrome) camera. The off-the-shelf solar-imaging solutions are much cheaper because they are designed for much smaller aperture and smaller image circles.

Given the brightness of the sun, a telescope with a huge aperture is not necessary and the cost of the various adapters usually outweighs the cost of a moderate solarscope-combo (even after you add some extras)

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LINKS to dowloads :

SharpCap2 : www.sharpcap.co.uk/sharpcap/downloads

FireCapture : firecapture.wonderplanets.de

wxAstroCapture: arnholm.org/astro/software/wxAstroCapture/#WINDOWS_INSTALL

AVIstack2 : www.avistack.de/download.html

AUTOSTAKKERT :

VirtualDub : www.virtualdub.org

Handbrake : handbrake.fr

TEncoder : sourceforge.net/projects/tencoder

VLC player : www.videolan.org/vlc/index.html

DEEPSKYSTACKER : deepskystacker.free.fr/english/index.html

REGISTAX6 : www.astronomie.be/registax/download.html

NOTES :

(#1) Shooting RAW, dSLRs can achieve 5..12fps -- but they cannot sustain that speed. Usually the buffer is large enough for 10...20 RAW images -- OTOH when streaming video, there usually is no buffer limit

(#2) When using a SLR on a telescope, you need to be careful to avoid vibrations from the shutter and that's another reason rapid-fire SLRs aren't a good choice for this type of observation

(#3) dSLR can record video -- but IT IS COMPRESSED and limited to 8bit/channel. For the post-processing the extra fine details are important and CCD cameras can provide uncompressed 8...12bit monochrome data at 15...60fps (and 1...2MPixels)

(#4) tethering a dSLR to a PC via USB can have unwanted side-effects. Depending on camera model & software it WILL NOT store images in the camera but all shots must be instantly downloaded to the PC -- that can take several seconds per shot.

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© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print

So you want to -- get a shot of the Sun or Eclipse

nobody@ipernity.com (Stargazer95050) — Fri, 17 Oct 2014 06:17:46 +0000

Stargazer95050 has posted an article:

Similar to lunar eclipses (/blog/stargazer95050/669999) you have different approaches. Timelapse versus still image. Close-up versus Wide-angle and here I won't describe these alternatives. What makes this different is you want to directly to look at the sun but "Mama always told me not to look into the eye's of the sun" -- But Mama, that's where the fun is !!

The solution is -- you knew that -- a good filter to block most of the light. And with most I mean approx 1.000th of 1%. Or even more. And not only the visible light but also the UV & IR as those too can burn your retina or heat & burn a camera sensor. But what filters ?

The example above is a GOOD VISUAL OBSERVATION FILTER -- it meets all the criteria and when you hold it up against your eyes, you have a good view of the sun & sunspots. This particular model is made of special glass. Other solutions include a variety of polymer, mylar or metalized films.

In any case, don't cheap out and spend the $1...$20 on a well-tested & manufactured visual-observation filter. It is fun to read what contraptions people come up to save a buck -- but your eyesight is worth this investment. NASA has a page highlighting UNSAFE DIY solutions : eclipse.gsfc.nasa.gov/SEhelp/safety.html

As always, checking the sellers reputation is important. Before first use, carefully look at the filter and check if you can spot leaks. Hold it up against a bright lamp instead of the sun. Hold it up against the sun and shine it onto a sheet of paper to check for leaks.

"What kind of filter", you ask ? The category to describe them is called "Energy reduction" filter. Also called (a bit misleading) "White Light" filters. The reason for "white" is, these filters aren't narrow-band filters and let all VISIBLE / WHITE light pass and (hopefully) also block UV & IR. In this category you still find many variations and the resulting image of the sun may have a greenish, yellow, orange, red or yes, you guessed it, white color. Scientist may favor the white-ish to analyze a color-spectrum -- I favor the yellow...red color. Not green. Not white. And that filter I showed above has some of the most pleasing colors : /stargazer95050/archive/created/2012/06/05

"What kind of filter" also has to consider what kind of lens or telescope you are going to use. Strapping cardboard in front of a big lens was an act of improvisation born out of desperation. With better preparation you can research and find filters to suit your lens. And for my telescope, I have a suitable solar ERF-filter : /stargazer95050/19370235 .

Once you put a solar-filter in front of a camera lens or telescope, you have a new challenge -- how do I find the sun ?? No -- that's not a joke. With the narrow FOV of a tele(scope) this isn't as easy as you may think because through this solar filter you don't see anything. It all is black -- only when you directly point at the sun, you see a small bright dot. So you're telling me, I shall not look at the sun and when I'm not looking at the sun, all I see is black -- how the heck will I find it ?

SUGGESTION (1) -- lots of patience and carefully & systematically scan the sky while avoiding looking at the sun without protection. Not as easy as it sounds, especiaslly when you don't have any added shade around your dSLR.

SUGGESTION (2) : BEFORE you add the blocking filter to your lens, you can REMOVE the camera and leave the front & rear of the lens open. Hold you hand or a piece of paper behind the lens and move the scope until you see the image circle of the sun. Lock the tripod position and put on a lens cap or the ERF filter and AFTER THAT attach the camera again. If you attach the camera first, you may melt the plastic on the inside -- NO KIDDING !!

This approach still requires a little bit of "hunting" -- the better you can secure the camera& tripod position while making the changes, the better.

SUGGESTION (3) : use a simple cardboard tube as your "finder" . Put it in place of your camera or telescope -- be accurate, it will save you time later. And now, instead of looking through, LOOK AT THE SHADOW it casts. The longer the tube, the more accurate but finding the sun also takes longer. As the tube starts to point at the sun, there will be a light inside the shadow -- likely at first it isn't round. Make your adjustments until you have a nice round "doughnut" shadow.

Now replace that tube and mount the camera + lens + solar filter and you have narrowed down the search area a lot. Ideally you only need small adjustments.

SUGGESTION (4) : uses the same concept as the cardboard tube but doesn't need any extras besides what you already have on your tripod. Use the vertical & horizontal pieces of the camera or tripod head and observe the shadow as you swing left--right and tilt up--down. When the shadows are at its thinnest, the camera points directly at the sun. This really cuts down time to find the sun and avoids looking directly at the sun.

Now you have your camera + lens + filter all assembled and it is pointing at the sun. What could go wrong now ? -- Glad you asked because FOCUSING is the next step (skip this if you use a AF-lens). And focusing itself is only the secondary problem -- the first challenge is to focus while you look at the viewfinder or rear-LCD when at the same time, the sun shines right into your eyes.

This, I improvised and it served me well through two eclipse shoots. Naturally there are dedicated "solar shields" and you can import them from Germany for 50 EUR a piece (Those are nice, yet simple flat sheets of metal, not cereal boxes)

However you decide to solve this, a towel/cloth, a bigger cardboard box, a laptop and tethered remote view -- this shield serves TWO purposes : a BRIGHT surface on the outside to reflect as much energy as possible and a DARK surface on the inside to avoid reflections and improve contrast.

SOLAR SHIELDS or HEAT SHIELDS aren't gimmicks -- some solar observation accessories are temperature sensitive. And you may not want to bake your SLR under the soaring heat & sunlight. And for visual observation, you also need shade to cover the ocular -- your choice how you provide that protection. On astronomy web-sites you can find $50 gadgets -- even a simple cardboard box can be used if you have a box cutter or scissors.

Especially solar filters made of glass have the annoying side-effect of a very reflective (rear) surface. As you hold up the filter against the sun, you see the sun - and you see yourself and everything bright behind you. With a box or (better) a thick, black cloth, you can block that stray light and kill these reflections.

When you think about eclipse and timelapse in one sentence, you have to consider the duration -- 180...330 minutes is the range you have to prepare for. If you want to shoot a timelapse this can mean as few as one shot per minute. Or you may see the need for HDR & bracketing and want smoother movements. 3 x HDR, every 10 seconds x 330 minutes ==> 10.000 shots will require substantial memory capacity & additional battery packages. Add to this 12V power for a motorized mount and (backup) power for the laptop controlling all this.: /stargazer95050/19371879

For shots covering such a long time, you likely want to use a tracking EQ-mount. Over the course of 3...5 hours, the sun covers a large area of sky and without a short-ish tele tracking the movement, the details of the eclipse will be very hard to see in the final wide-angle image. /stargazer95050/19498783 Naturally that mount needs (12V) power plus you have to polar-align it during daylight.

You can shoot an eclipse with many different setups -- and here you see how I mixed two options. The EQuatorial mount was tracking the sun (timelapse + laptop-control) while a separate, fully manual tripod + SLR + cable-remote-timer gave me additional opportunity to change the view and shoot things beside the eclipse. Naturally that tripod setup also is a lot easier to move and has a big advantage if you want to get a particular alignment.

There are many options and many different approaches lead to success. The issues I mention had caused me trouble and I think you have the opportunity to avoid some of these stumbling blocks. It doesn't mean you don't need to practice -- there are things that can go wrong during such a long shoot and with practice you are experienced enough to solve those issues quickly. "Luck favors the prepared"

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PROLOGUE : Let me remind you -- be very careful and take the warnings seriously. The concentrated heat of sunlight coming through a lens can melt plastic & metal. Even seemingly good filters can burn your eyes as they let UV & IR pass and you won't see or feel anything but massive, irreparable damage can occur to your eyes. Many of the DIY solutions to protect eyes aren't very safe.

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© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print

What to LIKE & DISLIKE about the EQ-6 Pro telescope mount

nobody@ipernity.com (Stargazer95050) — Tue, 30 Sep 2014 22:47:09 +0000

Stargazer95050 has posted an article:

From the ground up :

Important / distinguishing features of the Atlas EQ-6 Pro
Tripod
12V power
Mechanics
attaching & adjusting the mount during polar alignment
about the mount
ALT & AZ adjustments
Polar Scope & alignment
Balancing & Counter-weights
Clutches
Saddle
Cables & connections
Handcontroller
Orion's Software & Drivers
3rd party SW -- EQMOD & EQASCOM
MECHANICAL HAZARDS

IMPORTANT / DISTINGUISHING FEATURES

It is designed to be an EQ-mount, yet you quickly can quickly tilt the body (no extra tools or equipment needed) and use it as an Alt/Az mount -- e.g. for convenient setup & visual observation. By comparison, iOptron uses their mount head but you have to mechanically swap the EQ-base for an Alt/Az-base. That is a more laborious process, plus that extra base costs you another $150. If you want to add a 2nd saddle, iOptron charges another $190 while Orion includes it for "free" with the EQ-6 Pro.

IMO, I'd rather skip the 2nd saddle for a $190 savings, while the instant Alt/Az switch mechanic is a useful option.

The EQ-6 Pro comes with extra set of encoders -- they aren't real "absolute" encoders. This is a big upgrade and I'm evaluating that. Hopefully it lives up to the promises. It can reduce PEC and make adjustments easier (especially when you manually move the mount) and don't want to loose you previous alignment.

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THE TRIPOD

It is nothing to rave about and not much to complain about either -- a run-of-the-mill set of legs. It lacks the ability to replace the feet with a DIY, adjustable ones. Similar tripod, different foot ==> big improvement : /stargazer95050/28534127

There is considerable friction between the mount's base & the tripod. Therefore I'm adding a layer of TEFLON to smoothen the polar alignment. Maybe an even thinner layer of Teflon tape will do. I just happen to have these self-adhesive tiles (1/10" thick) and they do a good job. /stargazer95050/34772703

I DISLIKE the way, SKYWATCHER / ORION / CELESTRON lock the mount to the tripod using a center screw and combining it with the leg spreader. During polar alignment, you have to loosen the leg spreader, you have to (slightly) loosen the mount only to be able to make azimuth adjustments. In contrast, the iEQ45 uses a similar tripod & leg-spreader mechanism but the mount is attached to the tripod with three screws from the TOP instead of a single center screw from below.

FURTHERMORE : as you tighten the center screw, you likely alter the Azimuth adjustments you've just made during polar alignment. Not to mention, the feet may slip as you unlock the leg spreader.

That screw locking the mount from below the tripod's base makes it difficult to attach the ATLAS or CGEM to a pier. You always need access to that screw. It usually means extra plate to raise the tripod head. Cutting a hole into the pier might destabilize it.

The iEQ45 sits on a flat surface and has three screws to lock the mount to the base of the pier or tripod. These screws sit on top of the mount's base and fasten to the tripod -- that's opposite to the ORION / CELESTRON way.

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12V POWER

While other mounts top out at < 2A (@12V), the Atlas EQ-6 Pro demands 4A, possibly even 5A. That massive increase requires some big changes in the way I power the mount. None of my Li-Ion packs can power such a surge and even the small Lead-Acid batteries may not be strong enough to satisfy that peak current. Their capacity surely isn't enough to power a mount throughout the night.

Another obstacle is the very nice but HARD TO COME BY 12V connector. The absence of a 2nd source means, I cannot build my own DIY cable and have to use the 12V cigarette plug as an interface. Very frustrating since I just finished a cable tree to distribute the 12V.

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MOUNT MECHANICS

Compared to the CGEM, the iEQ45 was small and much lighter. The EQ-6 Pro is in the same weight class as the CGEM and this photo of the CGEM & iEQ45 will give you a good impression of the size difference. The EQ-6 Pro is slightly bigger than the CGEM : /stargazer95050/28460853

The Atlas EQ-6 Pro weighs ~35lbs -- the iEQ45, also rated to carry a 44lbs load, weighs 25lbs. The 10lbs difference is very noticeable as you carry that mount to a location.

The Altitude adjustment of the old CGEM was frustrating as two counteracting screws often messed up the setting. The EQ-6 Pro, like the iEQ45, use a single, long thread to control altitude adjustments. That is a big improvement.

The Atlas EQ-6 Pro looses points (compared to the iEQ45) for its inefficient mechanics to tighten the Altitude axis. The two screws to tighten the axis don't prevent movements. With a slight imbalance, there may be sufficient weight & friction to avoid problems.

FURTHERMORE, the (new) Azimuth-screw creates a new COLLISION HAZARD. It can catch dangling cables and also my USB-hub collided with that screw. That hub is cheap and also can be relocated easily. Your filter wheel, SBIG or QSI cameras are also at risk, Their cases significantly extend below their optical axis and below the telescope's rail -- no other mount has an obstacle in that area !!

Encasing the electronics, motors & gears inside a big metal body / mount is a good way to protect them. At the same time, this increases weight, usually uses smaller gears and make parts less accessible to the user. You purchase shows what option you prefer.

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Adjusting the mount during polar alignment

This is related to the MECHANICS above :

-) unlock the leg spreader --> feet may slip, especially on uneven ground

-) unlock the center screw to allow the mount to move --> mount may tilt slightly

==> there you have two serious problems already

-) after adjustments are done ==> tighten the mount's center screw. That screw often will slightly rotate the mount, thereby screwing up the AZ-position.

By comparison, the iEQ45 uses very similar tripod but the mount is attached to the tripod with three screws FROM THE TOP. You can loosen & tighten them with NO IMPACT on the legs and also NO IMPACT on the mount's AZ-position.

Personally, I prefer the center leg to point NORTH -- Orion ships the tripods with the center leg pointing SOUTH. No big deal -- you can move the peg 180°.

DISLIKE : The EQ-6 Pro does little to protect the polar scope from any mechanical impacts and dirt while the competition has some screw-on hoods. During unpacking, I nearly grabbed that polarscope like a handle to pull the mount out of the box.

==> IMO that scope deserves better protection since polar alignment is important.

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SO-SO :

Especially in Alt/Az mode, you can add a 2nd saddle to your setup to shoot or observe the same patch of sky with two different lenses. Or one camera & one visual scope. The EQ-6 Pro provides that 2nd saddle -- other vendors charge extra. Occasionally, it is a nice option to have and I might use it for a lunar eclipse shoot.

If I had the choice between saving $190 or the 2nd saddle, I likely would have skipped the 2nd saddle.

Both saddles are the same and you can attach your camera using the RRS/Acratech bracket but the camera will be in PORTRAIT orientation. If you have an L-bracket, you may be able to mount the camera in landscape orientation -- but that will interfere with the remote's cable. Not Orion's fault ! -- it was a bad idea by the camera's designers, they should have placed that cable-release & USB-connector elsewhere.

SO-SO :

Size of the gears also is a factor in improving accuracy -- Celestron & Skywatcher (Orion) keep the gear inside a bulky, metal case. That is good for protection but the overall diameter of the gear is smaller. iOptron, AstroPhysics & other use the opposite approach and make the gear big and place a smallish box with motor & electronics on the outside. The latter approach reduces weight (assuming same size gear) and/or cost (lower manufacturing precision achieves same mechanical precision) and better user serviceability (just pop of the cap to make adjustments)

Encasing the gear & electronic has advantages too -- that heavy-metal case protects the mechanics from rough transportation and the elements (dew & dust). It also deters user maintenance & modifications.

LIKE :

The counterweight shaft slides in & out of the RA axis of the mount. One less item you have to pack & assemble. The slide mechanism is an elegant solution. The iEQ45 also STORES the shaft inside the mount but you have to unscrew the shaft, pull it out and screw it back into its useful position. Small advantage for the EQ-6 (but it contributes to the higher weight of the mount when you carry it)

It is a very rare problem but occasionally, the camera is TOO LIGHT to balance the mount. Even with no counterweight, the small camera cannot balance the heavier mount & CW-shaft. With the EQ-6 Pro, you can slide the CW-shaft back into the mount, thereby shifting the balance. Also, the EQ-6's saddle is not as heavy as others, reducing the risk of such a problem.

LIKE :

After tightening the clutches of the EQ-6 Pro, there is no slack in the movement of the axis. With both the CGEM & iEQ45, I could very slightly move the RA-axis. Furthermore, there's no interference while tightening the clutch. Other mechanisms cause small movements on the axis as you tighten it. Both, Celestron & iEQ45 have that issue, most visible on their DEC axis.

LIKE :

The Altitude adjustment of the old CGEM was frustrating as two counteracting screws often messed up the setting. The EQ-6, like the iEQ45, use a single, long thread to control altitude adjustments.

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Polar Scope & alignment

To be honest, I am not really a fan of using a polar scope for several reasons. inconvenient access and limited visibility of the stars are two reasons. More : /stargazer95050/28462461 . Even after altering the tripod's orientation, the EQ-6 Pro suffers from many of the same drawbacks as the CGEM. I rate the iEQ45 higher for its illuminated double-crosshair and the nice visual display of Polaris & crosshair on the handcontroller display. A graphic display compared to 2 line text display

The EQ-6 Pro (Alt/Az) can make up for some lost ground when compared to the CGEM. For one, the polar-scope is standard, not a add-on and it is well aligned with the mount. And when it comes to COLLIMATING the mount & polar scope, The EQ-6 Pro's ability to adjust to (nearly) any angle from 0°...90° is very useful. Other EQ-mounts have limits or require more mechanical alterations ==> if you have a EQ mount and want to use a TERRESTRIAL OBJECT, it isn't easy : /stargazer95050/34556653 With the Alt/Az mount, pointing the RA-axis to a target close to the horizon is an easy feat ==> adjusting the polarscope during daylight becomes a whole lot easier.

As I mentioned before -- since I'm not a fan of using a polarscope, this advantage is less important to me -- you may find it more useful than I.

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BALANCING THE SCOPE & COUNTER-WEIGHTS

After hypertuning my CGEM, both telescope axis were nearly frictionless and you could easily detect small imbalances. And you could intentionally choose small imbalance to reduce backlash and keep consistent (small) pressure on the gear.

The iEQ45 added a new twist -- tilting both axis into a supposedly horizontal position. Not only was this an opportunity to measure the imbalance but also it was a (hidden) option to improve leveling & pre-dawn polar alignment.

Even when fully open, the clutches of the iEQ45 generated a lot of friction and therefore balancing the iEQ45 wasn't as easy as the (hypertuned) CGEM

The EQ-6 Pro has many similarities with the CGEM. Like the untuned CGEM, the EQ-6's axis don't turn as freely. And the EQ-6 lacks the neat feature to slew both axis into horizontal position.

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CLUTCHES

This is one detail, the EQ-6 Pro clearly outperforms both competitors. The CGEM as well as the iEQ45 use levers and as they fasten the clutch, there NEARLY ALWAYS is a movement ==> that ruins any previous, careful adjustments.

The clutches of the EQ-6 Pro are different. To lock or unlock, you have to turn an element which sits on the same axis. Tightening these clutches doesn't generate any force which makes those axis turn ==> a big improvement.

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SADDLE

There's a lot to like about the (smallish) EQ-6 Pro saddle -- and the only reason I am a bit concerned about it is the small size and the possibly large 44lbs loads that saddle is rated to carry. Other mounts use a much wider grip to secure such heavy loads ==> maybe I am just overly cautious.

BENEFITS of the EQ-6 Pro saddle : You can attach Losmandy & Vixen rails. IN ADDITION you also can use that saddle to attach RRS & ACRATECH rails : /stargazer95050/34576091 -- if you have a SLR, that can save you time, weight & money. Furthermore, the saddle's surface isn't flat as others. Instead some areas are lowered and that allows users to attach rails with protruding (center) screws.

The iEQ45 saddle has a nice detail -- there's an Allen-socket at the center of the screw. If you want to tighten it, that's the way to do it. The knobs on the EQ-6 saddle are quite small.

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CABLES & CONNECTIONS

The CGEM (again) is the negative example with a connector that may have been designed to fit a standard but the tolerances were out-of-bounds. Not everyone is willing to solder a new cable to fix that problem : /stargazer95050/34038339

The iEQ45 simplified the design because the DC-power plug wouldn't move. And that plug was a accurate standard size -- no trouble finding new, matching connectors.

The EQ-6 Pro has eliminated the problems caused by the CGEM-size AC-connector. Instead it has 2 distinct contacts and also a reliable screw mechanism. THE ONLY COMPLAINT is the lack of availability of a supplier for that type of connector -- so far no DIY cables.

The EQ-6 Pro has an extra output to connect to a (Canon) camera -- that is only a simple shutter release. Nowadays a USB connection is more useful.

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HANDCONTROLLER

It has a simple 2 line text-only display -- just like the other Orion & Celestron mounts and the arrangement of keys is nearly identical with other controllers. iOptrons controllers have a more informative display -- up to 8 x 20 char + graphic.

One serious disappointment in the EQ-6 Pro is THE LACK OF A BATTERY-BUFFERED CLOCK. No mount GOTO I have seen, lacks that feature. Now I have to manually enter date & time every time I switch on the mount. For a $2000, skimping on a $2 buffer battery is very disappointing.

The mount does not come with GPS -- you may add one for $150, but I suggest you don't.

If you want to connect the PC to your mount, you can use the provided RS232 adapter cable and plug it into the handcontroller and plug the handcontroller into the mount. That arrangement means you have to be careful not to trip over the RS232 cable whenever you use the handcontroller -- in comparison, iOptron places the RS232 connector on the mount itself. A solution I prefer. The cables don't move as the mount moves or you move around with the controller in hand.

With the EQ-6 Pro, you have the option to eliminate the handcontroller and directly connect the PC to the mount using a so called EQDIRECT adapter (plus matching EQMOD software -- see below)

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Orion's SOFTWARE DRIVERS

ORION provides their customers with a version of STARRY NIGHT -- and I find this a useful tool. The version I received did not include any "activation code" to grant me access to newly release satellite & meteor data -- older CDs included that key.

To make things worse -- STARRY NIGHT has good support for CELESTRON CGE(M). But it doesn't list the EQ-6 mount as available mounts. Therefore I decided to use CGEM settings even for the EQ-6 mount (the HW & SW come from the same source)

Ultimately, the best choice may be the EQMOD route -- the first attempts to switch the handcontroller into BYPASS mode seemed okay and I can use EQMOD as a ASCOM interface and use STARRY NIGHT plus the ASCM/EQMOD driver combo

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3rd party software -- EQMOD & EQASCOM

The original approach of EQMOD was to FULLY REPLACE the handcontroller and use the PC + RS232 to send commands directly to the mount. This approach was so successful, the new handcontrollers have an option to go into (seemingly) bypass mode and let EQASCOM send commands as if there was no handcontroller.

I have used that setup for a few nights and it works -- there may be some issues but I have to do more testing to pin-point those. It is possible the EQMOD and handcontroller commands may collide.

Abandoning the handcontroller is a tempting idea if you are convinced the EQMOD & EQASCOM is the better solution. The adapter cables cost ~$50 and you may want to add some extra money for a (wireless) controller to send slew command to the laptop while you look through the eye-piece (remember, EQDIRECT eliminated the handcontroller).

EQMOD also supports a combination of tools to reduce periodic errors: PERECORDER & PECPREP. The EQ-6 Pro has additional encoders on each of the mount's axis to better track their movements and reduce errors such as PEC. It remains to be seen how good that works and if EQMOD and the new encoders cooperate.

Older mounts likely will benefit from those free tools -- in fact there are several tools charging ~$150 or more to do the same job.

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MECHANICAL HAZARDS

The design of the mount brings a new hazard other mounts don't have -- the altitude adjustment screw sticks out like nothing else I've seen before on a mount. In that position it can catch any dangling (USB or power) cable. To make matters worse, I had rigged my refractor with a USB hub attached to the bottom of the rail -- now on a collision course with the altitude screw : /stargazer95050/33621317

Another new found hazard in the EQ-6 Pro GT involves the handcontroller cable. A big ferrite to improve EMI can get caught between the mount's base and the moving head. Especially when you operate the mount from a distance and keep the handcontroller in place, you have a good chance to experience that kind of "collision"

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© Copyright 2014, All rights reserved -- post a link to this page or contact me,

if you want to use it in your blog or publication or if you want a (large) print

Polar alignment -- what software works best ?

nobody@ipernity.com (Stargazer95050) — Tue, 23 Sep 2014 17:45:37 +0000

Stargazer95050 has posted an article:

Excellent question and I will list the tools I have tried and report back the results -- the listing here is more in a chronological order and doesn't represent a "ranking". In most cases, a ASCOM connection between the laptop & mount is needed and many tools also will use a ASCOM camera driver (NOTE : if you have a SLR, you do not have a ASCOM-compatible camera)

It is a work in progress -- I'll update the different sections as I have time to try the tools. The trouble I am having is the tools I have tried give me contradicting results. That's something I have to resolve first.

ASTROTORTILLA + APT (13EUR)

Astrotortilla's main duty is "plate solving" and I use it to confirm or correct slews to a target. It can control ASCOM cameras directly and also supports a separate image acquisition tool (APT) to use dSLRs as well as a ASCOM camera.

Seamless workflow from image capture with my (Canon) SLR, through solving & slew to the intended position made this my first choice. For polar alignment, I leave the mount in HOME position, switch off tracking and repeatedly solve the position as I make mechanical adjustments. AT will process the image and you should watch the solved position : It will show RA/DEC and with some practice and good preparation, it doesn't take long to point the mount 1/2°...1/5° from the NCP. Reading DEC you see the amount of the error, RA gives you the direction.

During preparations, I make sure the tripod is leveled -- usually within < 0.2° error.

PS : APT does more than "just" polar alignment and the 13EUR is a good deal for a useful tool. AstroTortilla is open-source & freeware

APT's built-in DARV (CCDalign) algorithm

The main concept here is to let the mount slowly slew at sidereal speed in one direction and later slew the same amount into the opposite direction. When your mount is accurately aligned, the startrails fully overlap. Otherwise you see a "V" and the width of that opening is an indication of the misalignment. You make mechanical adjustments and repeat the step. Once done, you have to do the same for the other axis and alignment star.

IMO that is a very elegant solution, taking advantage of the long exposure capabilities of the camera and delivers an easy to read indicator for the size of the error. It still requires more knowledge & interaction from the user as he/she has to select suitable alignment stars and slew the mount into position.

ALIGNMASTER (14EUR)

Unlike the other tools, Alignmaster doesn't require an imaging camera -- good news for visual observers. Of course, you can use the camera's rear LCD & Lifeview or stream the view to another app on your laptop.

The list of acceptable alignment stars is short -- but you can extend it (edit a text file). Based on date, time & location, the program will recommend pairs of alignment stars -- it doesn't take visual obstructions into consideration. That's your job. The procedure itself is simple : The tools slews the mount to a star's supposed position and you make the adjustments until the star actually is inside the crosshair. After that, AlignMaster will calculate the Altitude & Azimuth errors and slews the star off center. Turning the mechanical screws, you adjust the mount till the star again is in the crosshair.

You should repeat that until the errors are low enough.

AlignMaster's alignment sequence is very similar to the 2-star alignments modern GOTO mounts do. The mounts usually don't offer a easy choice of alignment star pairs (limited display).

PHD & PHD2

Many people use these tools for autoguiding -- the functions to help you with DRIFT ALIGNMENT are often overlooked. PHD2 has made that task more user-friendly. I think it will work similar to DARV / CCDalign in that you temporarily disable tracking and observe the deviation (and correct that).

WCS WebCamScheinern (21EUR)

This too is a tool targeted at a different group of cameras : (modified) streaming WEBCAMs. Recently they've added support for the models from ImagingSource (e.g. the popular DMK series)

EQALIGN

This _ONLY_ works with ASCOM cameras -- not with dSLRs. I'll try EQalign out later but would like a solution that works with both cameras.

BACKYARDEOS V3 ($50)

It's been a while since I used that -- it has an adjustable reticle to track the drift. I am not sure what further improvements the current version has. When I compared BYE to APT, APT won me over with the good integration of ASCOM + Canon camera support and AstroTortilla interface.

ASTROPLANNER

This too can use your time & location to determine suitable pairs of alignment stars. It also can communicate with ASCOM mounts, but I am having trouble with that setup. Especially when I include a ASCOM hub. Also, Astroplanner inquires various ASCOM features but some drivers have trouble with that. some mounts don't accept SYNC commands and Astroplanner uses those during alignment.

Sequencegenerator PRO ($100)

It can use PINPOINT ($150) & ELBRUS ($0) plate solvers and at least can accurately point at Polaris. Just as with APT. SGP supports dSLRs. Even some NIKON models !!

OTHER TOOLS

This list is by no means complete -- some tools are free but they rely in expensive infrastructure ("The Sky" "Maxim DL"). If I decide to make that leap, I'll try out those as well.

MY EXPERIENCE with these tools :

APT + AstroTortilla work really well together, both with ASCOM CCD and (Canon only) dSLR. After several comparisons with other tools & during the tests of polar alignment, I am not sure anymore about the accuracy of the reported position. And if the reported position isn't accurate, the polar alignment suffers too.

AlignMaster has a good reputation and the tool calculated errors much bigger than the error I was expecting ==> Now I am investigating what goes wrong and what result I can trust.

Maybe the only way to settle this is a god-old-fashion drift alignment -- but there are additional mechanical problems that can be involved. The mechanical setup of the mount's base now appears to be accurately leveled, I suspect there is some noticeable CONE ERROR and that can mess up the alignment.

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LINKS :

www.ideiki.com

sourceforge.net/projects/astrotortilla

www.alignmaster.de

www.stark-labs.com/phdguiding.html

openphdguiding.org/

http://wcs.ruthner.at/index-en.php

eqalign.sourceforge.net

www.backyardeos.com

astroplanner.net

www.mainsequencesoftware.com

www.astrosurf.com/pulgar/elbrus/elbrusin.htm

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© Copyright 2014, All rights reserved -- post a link to this page or contact me,

if you want to use it in your blog or publication or if you want a (large) print

So you want to -- get better images of the Moon

nobody@ipernity.com (Stargazer95050) — Sun, 14 Sep 2014 23:14:09 +0000

Stargazer95050 has posted an article:

Getting a tack-sharp, large-scale result like the above 2703x2231 pixel image isn't something that comes easy. Anyone, who has tried to get a close-up shot of the moon from a single shot with a dSLR will recognize that challenge.

Of course, focal length is one important factor to improve the resolution. But in this case, it is NOT the only deciding factor. Instead, the "secret" lies in the method of HOW TO get to this result. You can improve the final result by capturing many images and picking the best of them, or even just the best portions of all those images, to build a composite image.

To better understand the problem, you have to consider how the Earth's (turbulent) atmosphere can get in the way of (terrestrial) observation. You don't need a high- powered telescope to see that -- grab your SLR & 300mm zoom and you already can see the image of the moon being distorted and looking "wobbly" -- and it can look much worse than this : watch?v=PbGFN1rv2qw

One way of improving the quality is to collects just a whole lot more data -- and you can use simple algorithms to average out the results or you can use more sophisticated pattern-matching algorithms to correct distortions and align images. Furthermore, these algorithm break the image into many small pieces and measure the quality (sharpness) of each piece, match the various pieces from all the (hundreds) of frames you captured and later blend all that into a singlle high-res still image.

That sounds like an awesome and fairly expensive piece of software, doesn't it ?

Awesome - YES. Expensive -- NO !! The software I am using is AVISTACK and it is FREEWARE. (small nagging screen) -- there is the small issue of acquiring the hardware -- that usually isn't free.

The setup I use

you can use any telescope, use prime-focus or par-focal and attach the camera to an eye-piece. The larger the magnification, the more time it takes to cover the moon. Of course you gain more details
you want a real VIDEO camera, not a SLR or phone -- important is the ability to record UNCOMPREESED (AVI)-data. Since the moon is bright, you can achieve 10....50FPS sampling rate, depending on your computer HW, the camera and the resolution. My setup uses 15FPS (1280x1024, 8bit B&W) UNCOMPRESSED AVI. And I emphasize UNCOMPRESSED. MPG and others eliminate the tiny dots and include compression artifacts because they think stars are noise. You don't want to use a LOSSY compressions for this.

Recording uncompressed AVI generates ~ 1GB / minute ==> you better have a large (and fast) TEMPORARY storage. An external USB-drive make file transfer easier and avoids long wait times to copy the files from your out-door laptop to the PC for actual processing
To capture all those sequences, you need a program to control the camera, perform pre-programmed exposure sequences, etc, ... and most cameras come with some SW to do that.

SHARPCAP is a Freeware tool, similar or better than the tools I have seen in the camera bundles
With a sufficiently large HD, you can capture a single 30-minute stream of AVI video. Or you can capture 30 x 1-minute streams. Or 60 x 30sec streams. What is the difference ?

For once, the 30min file will be 30GB but the SD-card you use to transfer files only supports files < 2 GB (FAT32 limitation)

If anything goes wrong, you may loose 100% but only 1/30 or 1/60 if you "Divide & Conquer" : processing more but smaller files is more efficient
The 2GB file limitation was the first big surprise I encountered

Transfer times from the outdoor laptop onto SD-card and from ther onto the desktop PC were as long, or longer, than actual image capture. Having USB3 sure made a difference.
AVISTACK turns one video stream into one high-res TIFF or JPG. And it does align & merge the images within the same stream, it doesn't do anything beyond that.
After AVISTACK generate 30...60 still images, I use AUTOPANO PRO (you may choose free PTgui) to align & stitch together the final result.

Sometimes it is "good" to have a telescope mount that's not accurately aligned because the drift provides a "natural" & slow-moving motion you can use to scan stripes of the lunar surface. Oncee that slow drift is complete, you still need to slew to a new start position for the next pass.

While I have seen good tools to position the mount among the stars, I haven't yet seen (or searched for) a tool to analyze the moon's map and assist in navigating the lunar surface.

The technique I described here also can be applied to capturing (color) images of Jupiter & Saturn. The moon is a lot bigger & brighter, making it a good starting point to learn the technique. And once you mastered mapping the lunar surface you can go on and scout the outer planets ...

As you increase magnification -- for example by shooting through the eye-piece -- the benefits of the stacking approach become even more important.

.

LINKS to dowloads :

SharpCap2 : www.sharpcap.co.uk/sharpcap/downloads

FireCapture : firecapture.wonderplanets.de

wxAstroCapture: arnholm.org/astro/software/wxAstroCapture/#WINDOWS_INSTALL

AVIstack : www.avistack.de/download.html

AUTOSTAKKERT :

VirtualDub : www.virtualdub.org

Handbrake : handbrake.fr

TEncoder : sourceforge.net/projects/tencoder

VLC player : www.videolan.org/vlc/index.html

DEEPSKYSTACKER : deepskystacker.free.fr/english/index.html

REGISTAX6 : www.astronomie.be/registax/download.html

© Copyright 2014, All rights reserved -- post a link to this page or contact me,

if you want to use it in your blog or publication or if you want a (large) print

So you want to -- setup your new mount for the first time

nobody@ipernity.com (Stargazer95050) — Sat, 23 Aug 2014 06:32:00 +0000

Stargazer95050 has posted an article:

First of all -- after your new astronomy accessories has been delivered, it usually is overcast the next couple of days. Happens to everybody. Blame Murphy's Law. Even if it is overcast or cloudy, some tests you can do right away.

CHOOSE if you want the tripod's "center" leg to point North or South. If you plan to use the polar scope, a leg pointing south can make it harder to get to the polar scope. The further north you live, the harder it gets because of the steeper upwards angle there's less room for you to squeeze in. Celestron ships their tripods with legs pointing south, iOptron has the leg to the north. Changing the direction is easy -- there's a bolt screwed into the top of the tripod and that position indicates north. Unscrew it and screw it back into the thread in the position near the "north"-leg..

There's no wrong or right -- this choice is a matter of taste & convenience and I think the easier access to the polar scope is reason enough. With the leg pointing north, the counter weights sit above that leg and you don't stumble over a leg while accessing the camera & scope in "Home" position. Others prefer the leg to the south and use to to rest upon while looking through the polar scope -- either way, it is uncomfortable /doc/stargazer95050/28462461

It never is to early to add DIY improvements -- and even crude workmanship can result in excellent improvements. This very improvised piece of (self-adhesive) TEFLON can be attached to the top of a tripod. It will greatly reduce the friction to move the mount during polar alignment. YMMV, but I found this to be very useful and the total cost of this was < $10 for four sheets, 5"x5" sheets. Optionally, you can attach it to the bottom of the mount : www.ipernity.com/doc/stargazer95050/30276599

Level the tripods's base -- if you are lucky, you have adjustable feet like those I added. Without adding the (heavy) mount, these adjustments are easier but if you are on softer ground, the added weight later may impact the leveled setup..Now add the mount, tighten it down and tighten the leg spreaders. If you are standing on concrete the positions should not have changed.

LOOK AT THE build-in BUBBLE LEVEL -- does it indicate the mount's base is leveled? If not, don't freak out. Small errors are common and later we will see if the bubble level is wrong. Maybe the tripod legs weren't tightened enough, ... My preference is a separate bubble-level -- those are easier to read in darkness while using a flashlight.

Once "calibrated", you can use a marker to indicate the correct position of the bubble.

Another mechanical check you want to make is to confirm the polar-scope is accurately aligned to the RA-axis of your mount. This sounds a lot more complicated than it is and you can (should) do it during DAYLIGHT -- all you need is a (moderately) distant telephone or power pole. You should point that polar scope at that pole and make sure the top of that pole is in the CENTER marked NCP or with a crosshair. With an EQ-mount, you likely will have to be creative and significantly lower the front legs to get the opening of the polar scope to point to such a low angle.

Next you use the hand-controller to rotate the RA-axis and watch the cross-hair and the top of that pole . They should remain at the same position. ==> IF NOT, you will need to COLLIMATE / ALIGN the polar scope. For now we hope it is correct.

Just remember this procedure, every few weeks or after a bumpy ride to a location, you should check that alignment again. Otherwise all your (optical/manual) polar alignment effort using the scope aren't giving you accurate results.

If you can, put the mount into ALT/AZ mode or use the "balance OTA" mode to put both axis into PRESUMED horizontal position. If all goes well, the mount's axis really are both leveled. If not, you can adjust the feet or legs until they are. With an EQ mount you can rotate the base by +- 15° and watch if you see any deviations on the leveled axis. If you have a mount that can swing completely into a 90° upright position (real Alt/Az operation), you can attach the angle meter to the counterweight shaft or (BETTER) the telescope and rotate it 360° around the Azimuth axis. When leveled in both directions, the bubble should remain centered at all positions.

Especially if the weather isn't any good, you can use the time to prepare & test the connection to your computer, driver, ASCOM and other astro-software. Take your time and CAREFULLY CHECK if there are firmware updates. Often you find Yahoo user groups. And many other places too. Not every firmware update is free of errors and sometimes users complain about updates removing feature(s) they liked ==> take your time. If it isn't broken or you are using a brand-new product, chances are the update will only marginally improve your mount. If possible SAVE A COPY of the ORIGINAL FIRMWARE -- not all vendors & tools have that option. If you don't like the upgrade, you can switch back !!

When you setup the mount, have ACCURATE time (incl timezone / GMT-offset) plus the ACCURATE GPS position of your location. With one of my two mounts, the backup battery for the clock and to save the settings was no good -- but at first, I didn't know. Now I setup all parameters (time GPS location, ...) and power off. Wait some time ... 1hour or two. And power on again to see if the settings are still correct. You may want to keep an eye on these settings until you have confidence in the RTC and backup battery.

When you mount _ANY_ telescope for the first time, be VERY CAREFUL. In one case, the rail on the Celestron's telescope tube was a tiny bit too narrow and would have slid off the mount's head. Later I found out, this is a common experience with Celestron using a slightly narrower rail. Common sense dictates to be careful and not to let go of a heavy OTA until you've confirmed it is locked-down. When you use a mount for the first time, this is especially important and be prepared for unpleasant surprises

OTOH, sometimes there are unexpected pleasant surprises : out of curiosity I used a RRS/Acratech rail and to my surprise the mount got a good hold of that. Naturally I repeated that with several, similar lenses & rails and the result was the same ==> go try and see what fits !! Acratech & RRS are popular with dSLR users and it seems, the astrophotography community & manufacturers are catching on and make the necessary (small) adjustments to accommodate those rails.

Make sure you have all the accessories you need for a successful start (at home in your backyard / drive-way). Especially if you are getting started, it can be frustrating when you find out "xxx" is missing and you have to wait 3...7 days for it to be delivered. Below a short list of items you should have handy during your first night(s) out with a new mount (and possibly a new scope or camera too)

:

12V DC : not every mount comes with an AC power-supply. Do you have a portable 12V battery or did you order a P/S ? Think about AC extension cords, DC cables & adapters beforehand. To my frustration, I found the 12V DC plugs look similar but aren't always compatible.
RS232 connection : is still the most popular connection on telescopes, few use USB. Firmware updates nearly always require RS232 ==> get a GOOD adapter. Some stargazers swear by RS232 adapters with a chip made by FTDI.

Extra CABLES are a money-maker for the vendors -- not all vendors provide the "update" cables for free. Or simple extension cables can cost $30 when an identical $3 (phone) extension cable would do.
extra counter-weights : this can be a "big" issue when you try to mount a SCT tube (even without any extras) on your new mount and you never are able to achieve balance. BOTH of my mount required ADDITIONAL counterweights, one even required an extension (learning from experience, I had ordered that together with the mount)
mechanical tools : you've seen my references to angle meter / bubble spirit level. Allen keys of various (metric & imperial) sizes are frequently used.
INTERNET ACCESS : chances are, you need to download more than one update or look up an online manual or ask questions

Not all tests & setup needs to be done outside -- you can play with the new mount under cloudy skies INDOORS. And having the mount only a few feet away from a PC can make some SW setup & test of drivers a lot more convenient.

You can connect your PC & mount and for the first tests, indoor or daylight is just as good. Stellarium is one tool capable of talking to different mount without the need of a ASCOM driver -- try that. When you can slew the mount and see the position, you have taken an important first step andhave less trouble getting ASCOM communication to work. HINT : If you mount isn't listed, try Celestron CGEM and Losmand G-11 -- those settings help me to get my mounts to work.

BACKLASH ERROR (compensation) : The problem is a common one -- the attempts to solve it differ. Even with expensive mechanics, there is a certain amount of "lag" when you switch the direction of movement on each of the axis. With motors & (cascades) of gears, it takes a number of turns to make up for that slack before any of the motor's movements will casue actual movement of the axis.

The Orion / Skywatcher use a very basic backlash method -- you manually enter a value. How you come up with the proper value is up to you. Try & error is a good way and it can yield useable results.

The EQ-6 manual mentione a startig value of "05000" -- after some tests a value of "00330" gave be good results. I may have to refine that using a larger magnification but this correction has had a noticeable impact
Other mounts have a more interactive approach and move the mount one way and ask you to use the handset to compensate that movement.
PHD & PHD2 also determine the backlash -- I am not sure how much the on-board loagic will interfere. Especially if you add EQMOD

While you are at it, there are other mechanical details that need your attention & improvements. The more you can reduce these errors, the less frustration you have when it come to pointing at stars.

CONE ERROR(s) : You did your best and the mount points at location X,Y. But due to misalignments between the mount's head, the mounting rail and the telescope's OTA, you are looking at X+delta1.Y+delta2. (deltas may be positive or negative values)

Vertical / Up-down - errors you can find by placing the rail on a calibrated horizontal surface. The optical axis also should be horizontal. At the moment I use an angle meter and measure the OTA's angle and IMO that is accurate- & close-enough.

AN explanation video : www.youtube.com/watch?v=WatdQlPp22Y

So far, I have no test to measure / correct the sideways cone-error. Not to mention the mechanical challenges -- so far none of my rails or OTA assemblies has a way to make the necessary adjustments.

What telescope setup do you suggest, I SHOULD AVOID for Astro-Photography ?

nobody@ipernity.com (Stargazer95050) — Tue, 10 Jun 2014 09:42:20 +0000

Stargazer95050 has posted an article:

As the name implies, VISUAL is using your eyes & brain to capture and process images. And that is a fantastic tool and it can do things our modern cameras still struggle with. At the same time, visual observation also means your "exposure time" is short while with a camera it can take 1...10 minutes for a single exposure.

During those minutes, the Earth rotates, the stars move and for a visual observer that's not a big problem. We recognize this movement while our eyes sample images at ~10 frames per second. A camera in the same situation would capture the movement of the stars and record them as startrails and to avoid those, photographers use a motorized EQ-mount

Telescopes for visual observation may not have any motors at all and that isn't a bad thing -- it reduces costs & simplifies setup. Astro- photographers need much longer exposres and therefore require a motorized mount to compensate for the Earth's rotation. Big Alt/Az-models for visual observation also have motors to accurately move the mount, and occasionally track a position in the sky, but that still will not eliminate the "field rotation". Meaning, the telescope will keep pointing at the same patch of sky and the star in the center of your view will stay put. But all the other stars will run circles around that one : /stargazer95050/30333005

To see that effect, I suggest you use Stellarium and perform these steps

launch Stellarium and set the time to after sunset
pick any (bright) star you like and press "[space]" to center it
zoom in (press "[Ctlr] & [Up]") until the FOV shows ~10° -- exact amount doesn't matter
Press "L" 3 times to accelerate time
see the other stars rotate around the selected star
at the end of the simulated night, the star will set and the horizon will be leveled

To see the difference between an Alt/Az-mount and the Equatorial mount, you repeat these steps with one small change : after pressing "[space]" also press "Ctrl-M". That toggles the type of mount.

You will see the stars all remain in place and at the end of the simulated night, the horizon will appear at an odd angle.

The Alt/Az-mounts are popular with medium to large reflector telescopes and are offered at attractive prices. Again, there's nothing specifically wrong but you should be aware of the problems you may encounter when you try to utilize a setup tailored to visual observation and attach a camera to it.

This setup does nothing to eliminate the field rotation I mentioned above and it adds some peril to your camera. The fork mount has some clearance to attach a mirror-diagonal and eye-pieces, meeting the needs of a visual observer. Often that space is too tight to accommodate the necessary adapters and a bulky camera.

Sometimes owners place such mounts on a wedge to accomplish nearly the same as a real EQ-mount ==> also getting rid of the field rotation. If you are aware of this mechanical limitation or have made sure you can fit your camera between scope & fork, you can use a mount like this (plus wedge) for astrophotography.

The optimization for visual use extends beyond the mount -- it also affects the telescope and the combination of the two. It is a lot more convenient to look through an eyepiece that's 4'....5' feet above ground, and that's one reason why many telescopes intended for visual observation, place the eye-piece at the front instead of the back. The tube is nearly as long as the focal length and you stand upright next to the scope's open aperture as it points at the stars.

Other telescope designs place the exit pupil in the rear and as a result the eye-piece may be close to ground and will require you to look up at a steep angle. An EQ mount + camera are in such inconvenient position. The benefit of this design is a more compact scope. The tube only needs to be 1/2 ... 1/3 the focal length but the eye-piece for observation may be a lot closer to the ground.

A astronomer-novice also will overlook another detail -- one that rarely is mentioned in the glamorous descriptions. Newtonian & Dobsonian telescopes (intentionally) offer very little room to adjust focus..For one, the focuser is on the side and the focus-tube can intrude into the optical path. And second, you can directly attach an eyepiece and there's no need for a mirror-diagonal. Engineers took that into consideration while designing the telescope tube but unfortunately it means, you will not be able to get a SLR into focus simply because of mechanical constraints. You can't get the sensor close enough. Recently, there have been some exceptions -- a few Dobsonians advertise their ability to get a SLR-camera into focus. Very carefully read the data and better have a good return policy.

In comparison, telescope type used by astrophotographers attach the camera to the rear, where focuser tubes don't interfere. They are opposite to the central mirror obstruction and leave plenty of room to adjust focus or add accessories.

Even if you can manage to get your SLR + telescope into focus, please take a careful look at the setup and ask yourself if it is mechanically stable. Many eye-pieces are light-weight while a SLR is 2lbs or more. The off-the-shelf solutions aren't designed to adjust for such changes and achieving balance isn't the only issue. How will such a setup stand up to wind or shutter vibration ...

If you start, I recommend you pick a refractor first. The (big) reflector telescopes are tempting with their larger magnification but it takes time to learn and reflectors add a couple of extra issues you have to deal with

the larger magnification means, every mistake you make has a much bigger impact
you may be pushing the limits of your mount with that big tube
for best results with that large magnification, you better also have good polar alignment & auto-guider.
reflectors are more mechanically sensitive ==> need to collimate the two mirrors (plus camera)

One final example why starter kits and (low-cost) visual telescopes are not suitable for astrophotography comes from comparing the size of your camera sensor to the diameter of the tube of the eye-piece. A typical cropped sensor has a diagonal of 28mm. The tube is 1.25" wide and that's 31.75mm and it can be very long ==> the vignetting can be very serious issue.

The telescopes I'm suggestion feature at least 2"-wide (50.8mm) focuser tubes -- that larger diameter reduces the vignetting but still may not be wide enough to avoid visible vignetting on FX-size sensors (43mm diagonal) and that's why you find 2.5" & 3.0" focusers on the expensive telescopes. (PS : the impact of vignetting also depends on the focal length)

IN CONCLUSION

If you are interested in astrophotography, there are a couple of important reasons, for skipping certain categories of telescopes and mounts. These issues aren't so critical for pure visual observation

Mounts may not include any (motorized) tracking
Fork-mounts may have insufficient clearance for cameras at the rear of a telescope
BY DESIGN there always is field rotation in Alt/Az mount (if you put them on a wedge, they work just like a EQ-mount)
Newtonian & Dobsonian telescopes rarely have sufficient backfocus distance for a SLR
the widely used 1.25" focusers will increase vignetting, even on small DX-sensors
Many of these setups are wobbly even before you add a camera

Trying to take a cheap shortcut by attaching a $1000 SLR to a $200 starter-kit should give you some food for thoughts. If it would work, why would anyone buy the more expensive equipment ? And how come even average-quality SLR lenses cost $400, a sturdy tripod costs $400 and you may even choose to add a $200...$400 tripod-head.

If you thought those investments were worth it to support your SLR, please adjust your expectations on what GOOD ASTRONOMY equipment will cost. There are telescope accessories with truly astronomical prices but you can find very good quality at reasonable & moderate prices and I recommend you put those prices in relation to your camera & other SLR equipment. $200 telescope (incl tripod) vs $1000 camera doesn't seem right when OTOH you pay $200 just for a sturdy-enough SLR-tripod.

.

© Copyright 2014, All rights reserved -- post a link to this page or contact me, if you want to use it in your blog or publication or if you want a (large) print

So you want to -- polar align your telescope

nobody@ipernity.com (Stargazer95050) — Mon, 26 May 2014 19:12:35 +0000

Stargazer95050 has posted an article:

Despite it's advantage, many first-time telescope buyers shy away from an EQ-mount because of horror stories about the time needed to setup such a mount. And possibly because such an odd-shaped rig with weights & knobs looks intimidating & complicated.

While it is true, this step of polar-alignment can be very tedious & time-consuming, this usually refers to very high-precision setups (permanent pier or observatory). Casual observers can finish it a lot more quickly.

And of course, not every observer needs that same high amount of precision & effort and when performing polar alignment of his setup. It is important to distinguish the intended purpose. Startrails invisible when shot with a 50mm "normal" SLR-lens become streaks 50 times longer when shot through a (2500mm) telescope. Plus, usually a telescope's aperture ratio is 4...8 times slower than your SLR lens. Now you would need a setup that's 300x more accurate, if you want to have the same amount of visible error in your images.

That's where some of the stories about time-consuming setup originate -- and as errors get smaller, the effort reduce them takes more time.

"Point the (RA)-axis of your mount (or StarTracker) at Polaris -- DONE". When you read that, it sounds simple. And it really IS THAT EASY but it also is NOT ACCURATE, though for many users it is ACCURATE ENOUGH. Polaris isn't at the CNP (Celestial North Pole), instead Polaris rotates around it, off by 2/3°. That's not much if your startrail image covers 60°x40°, but it is a lot when your FOV is as narrow as the full moon's 1/2°. With the use of a polar-scope with alignment-markings, you can increase precision, but these scope too come with their own drawbacks (more later)

STEP 1 -- applies to all and this may be all you need, to avoid startrails with a wide-angle lens. The advantage is, this works during daylight, doesn't use stars and instead solely relies on accurate mechanical & terrestrial measurements. Tilting the axis / lens based on your latitude and with the help of compass & maps, you point accurately north (don't forget the magnetic declination). The emphasis here is ACCURATE MEASUREMENTS.

If avoiding startrails is your goal and your FOV is wide, a small error isn't a big issue. Vixen's Polar Meter falls in that category and suffers from the same mechanical limitations. Altitude scales don't even show individual degrees. It is ACCURATE ENOUGH for the purpose of avoiding startrails with a wide-angle lens and POLARIE or ASTROTRAC. It's not a tool to align a telescope -- a wide-angle view is more forgiving.

It also helps, if you have prepared for that task in advance -- scout the location on Google Earth to find usable landmarks for orientation. Preferably some due north. If you travel, save the screenshots.

=====================================

The steps below all are done to further improve accuracy and I recommend those for photographers with narrow FOV (measured in minutes instead of degrees) and long exposures (measured in minutes instead of seconds). You still can choose put in less effort into leveling & polar-alignment to let the GOTO-mount do the necessary (goto & tracking) corrections for you (after a proper multi-star alignment sequence) but sloppy setup still can result in some residual image-rotation errors & elongated stars.

Leveling the tripod's or pier's base isn't a requirement. You can get perfect alignments even if the mount's base is tilted. All that counts is the RA-axis of the mount has to be parallel to the earth's axis. But to get there, you have to measure and make adjustments. With a (perfectly) leveled base, you make an adjustment and only one axis is affected. Simple cause & reaction relationship. The more the base is tilted, the more a single adjustment affects both axis.

Even if you use the GOTO alignment procedures, a properly leveled and north-aligned mount makes life easier to FIND THE ALIGNMENT STARS. If your mount is tilted 1° in each direction, you are 1.41° away from your intended target position -- but you don't know which way. Add to that e.g. a 1° alignment error between the saddle and the OTA or an additional cone-error and you may not even see the alignment star in the wide view of your finder-scope. It also means, later, the GOTO has to do more & bigger adjustments and there casn be image rotation.

If you want to follow my suggestions, you have to make sure the base REALLY IS ACCURATELY LEVELED. To get there, you will have to make very small adjustments and at some point, adjusting the tripod leg's length wasn't practical. Adding $3 worth of screws & wingnuts made life a whole lot easier. Paul Chasse has perfected that idea by adding a swivel foot and send me a triplet for testing : /stargazer95050/29051567. With other tripods, you may have to use thin washers, shims, ... to raise the feet.

Make sure the feet are on solid ground and don't sink in under the weight of the big setup. Spiky tripod feed (or these screws) are the worse. If in doubt, use tiles to spread the weight of the foot over a wider area of grass or sand.

With an accurately leveled base, setting up the rest of the mount has become one step easier, especially with the iEQ mounts. Thanks to a function which is intended to balance the mount & tube, but I "mis"- use it to determine the accurate "ZERO" position. Based on the GPS coordinates, the iEQ-mount places both axis into (supposedly) horizontal position. If your base is leveled and your "zero"-position is accurate, both axis will be leveled as well -- once the zero-position was accurate, I haven't seen more than +-0.1° error. And that is the accuracy of my angle meter.

During the first setup & after mechanical (alt)-adjustments, the zero-position may not be accurate and the balance-position isn't leveled anymore. If the axis aren't leveled as they should be, loosen the clutches and make adjustments. Afterwards, slew back to zero-position.

Polar alignment & zero-position are intertwined and whenever you make mechanical adjustements to the mount or tripod's feet, that can affect the zero position. With good preparation, these errors are small enough for a mobile setup.

PS : there are additional errors you may want to eliminate :

- collimate the OTA's optical axis to match the saddle / mounting rail -- eliminate the cone error.

- collimate the polarscope to match the RA-axis (if you use it) : groups.yahoo.com/neo/groups/ioptron-imaging/files -- "How To Focus and Collimate the iEQ45 Polarscope.pdf"

=====================================

I freely admit, these steps take extra time. But the important part is, these steps SAVE TIME when it is important to an astrophotographer -- after dark. You can improve the setup before nightfall. With proper solar filter & caution, you can even use the sun to do drift alignments. Once the stars become visible, there are several routes to finish the accurate polar alignment. IMO they all perform faster with this preparation.

do nothing else : your mechanical preparations already may be accurate enough for your task. Visual observation & wide-angle shots are good examples
use GOTO-alignment : your chances of finding the alignment stars improve the more accurate the mount is prepared. The better the polar alignment, the lower the raining field rotation.
further refine the mechanical alignment using the polar scope -- as a matter of personal taste, I dislike it because of inconvenience (I'll explain that later, with the tall pier & iEQ mount it became less inconvenient)
further refine the mechanical alignment using drift alignment -- there are many description & tools covering that. Drift alignment takes time and is done after sunset -- use of a PC & camera can help to reduce the time needed and simplify the procedure.
further refine the mechanical alignment by plate-solving current position
use plate-solver to SYNC the scope's position -- given the effort to prepare an accurate setup, the remaining errors may be quite small. I have used both methods but haven't done a comparison if there is a big benefit to further mechanical adjustments over a simple SYNC.

A lot depends what you will be doing later.and what amount of magnification & exposure times you will be using. Without auto-guiding, you rely on the precision of your setup and the optional GOTO-calibration. Auto-guiding (plus GOTO-calibration) can help to make up for some inaccuracies, field-rotation errors still be an issue.

My recommendation is biased -- not because someone paid me but because it eliminates the uncomfortable use of the polar-scope, it works smoothly and it doesn't require any new investments. But that assumption of "doesn't require any new investments" isn't true for everyone.

You shoot wide-angle images, you can get away with decent (purely mechanical) polar alignment and don't need all this
you can use a combination of good mechanical setup + polar scope -- once you have calibrated that setup
If you use a motorized GOTO-mount + dSLR but dont use auto-guiding, you likely don't have the laptop with you and my suggestion is less suitable for you.
if you use auto-guiding, you are likely to have a laptop with you and adding the plate-solver and hooking up your SLR can be accomplished quite easily

==> you want to see the practical advantage of adding a plate-solver : /stargazer95050/28668501

The optical POLAR SCOPE is a classic accessory to all EQ-mounts. It has Polaris & the stars of the "Big Dipper" marked in its sight and once you have matched all the stars with their markings, you have achieved POLAR ALIGNMENT. And I don't dispute that.-- if the scope is collimated to match the mount. Even with a brand new mount, that is not always the case. Detour : Align a polarscope

The other issue I have, it is very inconvenient to use because often the eyepiece is ~3ft above the ground. And you have to stare at an odd angle upwards trying to see stars, all the while you also have to twist knobs to move the mount into position. Did I mention, I wear eyeglasses and the scope hasn't much eye-relief ? Move your eye and you cause parallax errors. All that is a lot of hassle by itself IF YOU CAN SEE THE NORTH STAR.

For observations under a dark sky with eyes well adapted to the darkness, some issues would go away, the hassle of kneeling in front of the scope while adjusting would remain.

When in its "zero" position, the shaft for the declination axis is blocking the view of the polar-scope. That means, you can see Polaris through your telescope but not through the polar-scope. Based on the mount & model, you have to turn the DEC-axis 45° or 90° degree to open a window in that axis but naturally that eliminates the view of Polaris through the main OTA.

PS : these optical polar scopes usually cost another $100...$200 and guess what -- when sold separately, they need CALIBRATION to align with your mount & camera and you are the one to do it. I cannot tell how long these adjustments last and if you have to correct those when you frequently transport the mount.

UPDATE :

AlignMaster is a small but helpful tool -- especially helpful if you have your mount connected to a laptop. Based on time & location, it will suggest alignment stars and slew to the expected position. You manually center the star (using eye-piece of camera) and AlignMaster will record the offset. After checking two stars, the tool can determine the error and will aid you in making the mechanical adjustments. To improve accuracy, you should repeat that sequence until the error is small -- e.g. < 1...3 arc- minutes. It is very similar to the GOTO calibration procedures WITH ONE IMPORTANT DIFFERENCE : the corrections are made mechanically to the mount not corrected electronically through the GOTO-electronic.

Additional SW-tools to help with polar alignment : /blog/stargazer95050/781309

Having to FIRST CALIBRATE the polar scope defeats the purpose -- maybe that's another reason, the GOTO-alignment has increased in popularity

The best option, so far, involves image capture and software to perform "Plate Solving". Just like the results you get from submitting your images to /groups/astrometry. To be useful in the field, this tool shouldn't be web-based. Instead it must deliver results within a minute compared to hours for the flickr results ==> Laptop is required. Since I'm imaging & guiding, a laptop already is part of my setup. The software itself is free.

Using your CCD-camera or dSLR, you capture an image and feed it into AstroTortilla and that in turn will calculate position of the the center of the FOV. Adjust the Alt-screw and rotate the mount as needed to get close to the NCP. No need to kneel in the cold dirt to look through the polar-scope. On the left, a screenshot from the close encounter with CNP -- before I ran out of "solvable" stars ("thanks" to light pollution). Any further small adjustments were unsolvable -- bigger adjustments throwing the FOV further away from CNP were just fine as was using a scope with a wider FOV

More on successful & instant "Plate Solving" using a laptop : /stargazer95050/20413811

The crux with my particular setup, the FOV is very narrow and right around the celestial north pole, there aren't that many stars..POLARIS is 2/3° (or 40').away, thus of no use with this very narrow FOV (small camera + long focal length). In startrail images you won't notice that small distance, but at high magnifications, Polaris doesn't even show in my viewfinder (marked red & yellow) when I correctly point at the CNP.

A lens with a wider FOV shouldn't have the same kind of trouble and capture sufficient number of stars. A darker location surely will help. Maybe I also should be using a LPS filter ?

UPDATE :

If you are interested in PLATE-SOLVING, there is an alternative to AstroTortilla -- one that is easier to install. Open-source ELBRUS plate solver : groups.yahoo.com/neo/groups/StarLocatorElbrus/files or try mainsequencesoftware.com/Content/SGPHelp/SettingUpElbrus.html

Elbrus is a small windows executable ~2MB -- AstroTortilla is a LINUX-tool and you need Cygwin to run it on your Windows-PC. It is free but cost you ~300MB of disk space.

Elbrus database is ~1GB -- AT has more flexibility and you have to choose different catalogs based on the FOV of your scope + camera combo. My selection uses ~3.5GB to cover everything from widefield to narrow FOV with a 600...2000mm focal length.

APT & AstroTortilla work together hand in hand -- similar SequenceGeneratorPro has incorporated Elbrus into their workflow. Both Elbrus & AstroTortilla can be used standalone -- send them a JPG as input.

Hopefully I can get Elbrus to deliver similar good results as AstroTortilla / Astrometry -- for now I have to check Elbrus' results twice and at times there are massive discrepancies !!

.

1st published -- Dec 2013

update -- May 2014

added ELBRUS & ALIGNMASTER -- Sept 2014

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