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Light Weight, Portable, Low Cost EAA Setup

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#1 CA Curtis 17

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Posted 14 June 2016 - 11:41 PM

Having done EAA for 6 years now, I have always used an EQ mount and typically use my C9.25" or my C14" with Hyperstar.  And I am very happy to continue using these with my variety of cameras from my first, a Mallincam Xtreme, to my latest a Starlight Xpress X2C.  

 

However, I notice many who are either just getting into EAA and want to start with something relatively inexpensive, or just want something that is lightweight and easily portable.  So, as my personal form of public outreach, I got hold of a Celestron SE6, a Revolution Imager 2 and a ZWO ASI224MC to demonstrate what could be done with a light weight setup that is easily transported assembled from the garage or house to the driveway or back yard.  Others have posted with setups like these in a number of different threads (Charles comes to mind for one), but I thought it would be nice to have it all in one thread.  Hopefully, in addition to pulling all the information into one thread (and I assume others will add their inputs) this can become a resource for many new to EAA.

 

Why the choice of the SE6?  Well, first, it is an Alt-Az mount which represents a new challenge for me since I have only had the pleasure of using EQ mounts.  Most already know that Alt-Az mounts don't track along the Celestial Equator like and EQ mount does, so field rotation becomes an issue for long exposures.  How long?  That depends on the focal ratio used, the Altitude and the Azimuth of the object being viewed, and the observer's latitude.  At the north or south pole, no problem.  At the equator, the worst case for rotation.  Rotation follows the simple formula:

 

         Field Rotation Rate (arcmin/min)  =  15.04 COS(Latitude)*COS(Azimuth Angle) / COS(Altitude Angle)

 

So looking due east (90deg Azimuth) or due west (270deg Azimuth) there is no field rotation at any altitude because the Cos is zero.  However, that lasts for a brief moment before the sky rotates and you aren't pointed due east or west any more.  Looking due south or due north, field rotation will be the strongest.  And higher altitudes cause more field rotation in a given time than object along the ecliptic.  On my web site listed below you can find a nice graphic showing curves of field rotation for different Altitude and Azimuth angles.

But, as Charles and Astrojedi have pointed out and shown, using an Alt-Az mount with software which can rotate frames while stacking, one can overcome the field rotation problem to a great degree, i.e. take much longer exposures with this software than without.

 

Second, Alt-Az mounts are typically much less expensive than EQ mounts which goes to the low cost factor.  The 6SE typically sells for $799 including accessories, but I believe it is currently on sale for $699.

 

Third, there is no requirement to polar align an Alt-Az mount which makes it much easier and faster to setup than an EQ.  (You cannot polar align an Alt-Az mount even if you wanted to). The 6SE has a Skyalign routine which only requires one to go to three bright stars in the sky which are first aligned in the unity Red Dot Finder and then in the 6" scope and EP to get a GoTo alignment.  You don't even have to know which stars you are pointing at, just that they are far apart in the sky.  Once aligned, the hand control will even tell you which stars you aligned on.  How easy a setup is that?

 

Fourth, the 6SE comes with a 6" SCT which I think is sufficient for observing all of the Messiers and many of the Herschel objects with either of the two cameras listed above.  By showing what can be seen with this scope, one can reasonably guess how much more they might see with the bigger 8" but also portable scope if they are willing to spend a bit more.

 

Why the R2 and the ASI224?  Simply cost.  The R2 is $300 and the ASI224 is $349, which are two of the low cost options for EAA.  The R2 is an analogue camera which comes as a kit with a 7" LCD, Li Ion battery, focal reducer, UV-IR filter and cables.  It is a very good, reasonably sensitive camera which can be used with or without a computer.  The ASI224 is a USB camera which comes with a USB cable, C-Mount adapter and an All-Sky lens for wide angle shots of the night sky.  It requires a computer, but only a single cable.  And, if you decide to move up in cameras later, the ASI224 can be used as an autoguider.  And, given its very low read noise, it is very well suited, as others have shown, for stacking with software such as Sharpcap or AstroLive.  Did I say AstroLive is free with the ASI224?  Well it is.

 

So, over the next month I hope to post images with the 6SE with both cameras taken from my suburban back yard and from a dark site to give anyone interested an idea of what they might expect to see with one of these setups.

 

To get started here is a picture of the R2 setup with the 6SE.  I'll post a picture of the ASI224MC setup this weekend.

 

Here I have the camera attached to the SCT visual back with a 1.25" diagonal to give enough space for the camera to clear the mount when pointed at the zenith.  The Hand control is attached right at the back of the camera since I would be standing there to control the camera and view on the LCD.  I bent the LCD mounting base to the curvature of the the optical tube assembly (OTA) and glued a piece of spongy material to the bottom of the mounting base to avoid scratching the finish of the OTA and held it in place with velcroe straps.  I can change the angle of the monitor to compensate for different OTA orientations. I mounted the battery to the arm of the Nextstar SE mount and ran the power cable to the monitor and camera using the included power splitter cable.  The mount can be run on its own internal batteries or with an external 12V battery using the cable you see on the EP tray.  Excess video cable is wrapped around the LCD base to prevent snags.

With this setup, I can leave everything connected and stored inside my house and very easily carry it outside and set it up in under a minute.  Plus, the SkyAlign feature allows me to align to 3 stars in less than 5 minutes.  I did the SkyAlign with the video camera, since this is how I always align my EQ mounts, but it is a bit trickier since the object moves quickly across the LCD screen considering that this is an Alt-Az mount and the camera is equivalent to an 8mm EP.  I found it easier to use a longer focal length EP to do the alignment, but it very much can be done just with the camera.

Hope this thread is helpful to the new folks or anyone considering a low cost (relatively), light weight, portable setup.  Keep in mind that you can also use a smaller scope, including a refractor for even less cost or you can move up to a larger aperture or the Evolution mount for a bit more.

Best Regards,

Curtis

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#2 JonNPR

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Posted 15 June 2016 - 03:15 AM

Curtis, i applaud your initiative and project. And very much look forward to your progress, reports, and opinions. Personally, I am most curious what you will make of and decide about the 224. 

 

One bit of advice about the SE mount and alignment. You will find excellent advice and information about any issues with it on the Celestron forum here on CN. In particular, Tel will always be willing to track down any issues and likely point to the best solution. Roel, likewise most helpful and knowledgeable, just to mention two among many.  

 

I will offer one suggestion, that you consider using the auto two star alignment option. It is the consensus best of the several options offered through your handset, from what I have gleaned from several years of discussion by the observers on that forum, and my own experience - for what that is worth.

 

Best of luck, and I hope you have a plethora of starry nights!

 

Jon 



#3 mclewis1

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Posted 15 June 2016 - 08:29 AM

Curtis,

 

Nice discussion on a great setup.

 

If you want to investigate even lower cost options you might consider one of the following cameras ...

 

Mallincam SkyRaider AGm (or one of the other sources for the ToupTek GCMOS camera) -  $200 and in some cases under $150. You can use SharpCap and it's stacking capabilities with these cameras but you can also run the included software that has other noise reducing features instead of stacking.

 

ASI 120mm - the older USB2 version using the same sensor as the Touptek camera -  new $240 but many used models available under $200.

 

I've listed only the monochrome versions as it might be interesting to see mono options along side the two color cameras. Plus the two color cameras you're using are IMHO better color choices than the color versions of the cameas I suggested.



#4 CA Curtis 17

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Posted 15 June 2016 - 08:44 AM

Jon,

 

Thanks for your kind words.  Excellent suggestion on information about the Celestron forum.  I actually wondered over there recently and found out how to balance the OTA on the Alt-Az mount - I had no idea that it could be balanced but then it is actually so simple.  I appreciate any input or other tips on this mount/scope combination.

 

As for the auto 2 star alignment option, I will give it a try.  However, since I am directing my efforts to the new folks I like the SkyAlign procedure since it requires absolutely no knowledge of which stars are which.  I love that!  Even if the purists might cringe.  My point is, it takes all the intimidation out of the process so someone new can just start quickly to enjoy the night sky.  If they like it, I'm sure they will eventually begin to learn which star is which.  And, if they don't, so what, at least they are getting out to see the stars.

 

Marc,

 

Thanks and I appreciate your suggestions and hope anyone reading this thread and looking to get into EAA will consider those camera options.  I only have the 6SE for a short while so I only plan to focus on the R2 and ASI224MC.  I think that gives folks a starting point for either a video or a USB camera.  And, I love color so will stick with color cameras for now even though I really am impressed with the detail I see in images taken with the B&W cameras.  Heck, if one is doing narrow band EAA, might as well just use a mono camera for more light gather power as well.

 

Best Regards,

Curtis



#5 JonNPR

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Posted 15 June 2016 - 12:10 PM

Curtis, regarding balance, be careful not to literally balance the OTA! It needs to have a bit of front or rear heavy positioning for the gears to more easily mesh. And useful to determine and know which you choose for finding your preferred choice of altitude final go to approach (positive or negative) in your hand control settings. Preferred as in, works better.

 

About sky align. This isn't about being a purist! I understand your abstract thinking that Sky Align is "simpler". But in practice, in the field, that is often not the case in the collective experience in the forum. Also, you will find that getting the SE to track and go-to well, meaning without lots of frustration, has extra importance when you mount a narrow field of view camera on the scope. Experience of many Celestron owners suggests your results will be less frustrating if you use auto two star. Sky align seems less reliable for many, causing lost time observing and more fiddling. 

 

Your mileage may vary! I just wanted to be clear that the SE mount can be very good for EAA, but it also usually requires care in order to do its job, just as one must be careful to select the correct location and time, daylight savings (or not!), and determine each scope's unique anti backlash settings in the process. 

 

No matter what, wishing you lots of success,

 

Jon

 

edit spelling


Edited by JonNPR, 15 June 2016 - 12:11 PM.


#6 CharlesC

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Posted 15 June 2016 - 12:22 PM

Curtis,

 

I think your R2/ASI224 comparison with 6SE will be of great service to those looking at portable entry level EAA.  I'm curious as to how well the 6SE can handle the ASI224.  The 6SE requires 10 seconds or less (preferably 5s or less) when stacking with SharpCap and though ASI224 owners claim short exposures can be done, it seems most pics in gallery are using much longer exposures.  Can the ASI224 work well with 6SE?

 

I second vote for "Auto Two Star" aligning.  I pick Polaris first because its easy to find,  then computer lets you select a list of adequate 2nd stars,  then the computer automatically slews close to that second star.  Usually its not to far from second star and easy to finish alignment.  Its fast, easy, and accurate.  If you can find Polaris using Big Dipper, its a snap.

 

In regards to long exposures with 6SE,  I have taken 20 second stacked exposures with 6SE, but only with internal LN300 stacking set to maximum DNR=3.   With DNR=3, the LN300 has a sliding window average of three frames.  I've waited as long as 10 minutes to have three consecutive good frames averaged.  This can't be done with SharpCap.  This limitation isn't a problem with R2, but will it be with ASI224?

 

Look forward to your results in the future.


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#7 Robrj

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Posted 15 June 2016 - 01:38 PM

Curtis, is the purpose of this thread to showcase any low-cost, portable setup or just your experiences with the 6SE? If we have a low-cost portable setup, should we add it here?

#8 CA Curtis 17

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Posted 15 June 2016 - 04:10 PM

Jon, Charles,

 

Thanks for your practical advice based upon your hands on experience.  I will take it to heart.  More importantly, anyone reading this thread looking for advice on the SE or other Alt-Az mounts for EAA should consider the advice others more experience with these types of setups.

 

I have only has a few hours playing with the ASI224MC on my C9.25 on an EQ mount so I still have lots to learn about it, let alone how it works on an Alt-Az mount.

 

Robrj and anyone else,

 

Please feel free to add anything you want about other low-cost and portable setups.  The objective is to share with others, especially those just wanting to get started in EAA.  I chose a single platform with 2 cameras to showcase this approach to EAA because I can.  I don't have access to other setups myself.

 

Regards,

Curtis



#9 ChrisFC

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Posted 15 June 2016 - 06:27 PM

Curtis,

I think your R2/ASI224 comparison with 6SE will be of great service to those looking at portable entry level EAA. I'm curious as to how well the 6SE can handle the ASI224. The 6SE requires 10 seconds or less (preferably 5s or less) when stacking with SharpCap and though ASI224 owners claim short exposures can be done, it seems most pics in gallery are using much longer exposures. Can the ASI224 work well with 6SE?

I second vote for "Auto Two Star" aligning. I pick Polaris first because its easy to find, then computer lets you select a list of adequate 2nd stars, then the computer automatically slews close to that second star. Usually its not to far from second star and easy to finish alignment. Its fast, easy, and accurate. If you can find Polaris using Big Dipper, its a snap.

In regards to long exposures with 6SE, I have taken 20 second stacked exposures with 6SE, but only with internal LN300 stacking set to maximum DNR=3. With DNR=3, the LN300 has a sliding window average of three frames. I've waited as long as 10 minutes to have three consecutive good frames averaged. This can't be done with SharpCap. This limitation isn't a problem with R2, but will it be with ASI224?

Look forward to your results in the future.


The comparison will be interesting.

I have the original RI and a 224. With no filters I mostly use the 224 at x350 8-15sec and stack. If i drop to x300 then i use 15-20sec exposures. Similar exposures as the RI?

#10 alphatripleplus

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Posted 15 June 2016 - 10:12 PM

Curtis,

 

I think your R2/ASI224 comparison with 6SE will be of great service to those looking at portable entry level EAA.  I'm curious as to how well the 6SE can handle the ASI224.  The 6SE requires 10 seconds or less (preferably 5s or less) when stacking with SharpCap and though ASI224 owners claim short exposures can be done, it seems most pics in gallery are using much longer exposures.  Can the ASI224 work well with 6SE?

 

 

Most of my individual subs with the ASI224 (used in much longer stacks) have been short 5-7sec exposures at high gain (300-350). Looking at most of my posts, my subs are:

 

             7secs @ f/5- f/6 with 102Mak

             5secs  @ f/3 -f/4  with C8   

 

Some other users may be using  lower gain, with longer subs, but I believe Astrojedi and RafaelP have also used the ASI224  with similar 5-7sec subs at high gain. 

 

With my ST80 reduced to f/2.1, my subs were 2sec - sky background blows out at much longer sub exposures. The low read noise of this camera at high gain makes short sub exposures very doable.

 

Edit: I see when I first started using the ASI224 with the 102Mak @f/6.1, I also did some 10sec subs @300gain , but I've settled on 7sec @ f/6.1 and 350gain for the 102Mak.


Edited by alphatripleplus, 15 June 2016 - 10:17 PM.

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#11 CA Curtis 17

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Posted 15 June 2016 - 11:55 PM

Here are some of my first images taken with the R2 on the SE6 SCT from my suburban back yard.  I used the 0.5X focal reducer than came with the R2 which would give approximately f/5 although I have not yet measured this focal ratio exactly.  Average skies, moon setting in the west.

 

First some easy, birght objects, globular and open clusters.  These were taken without stacking.   Camera in Fixed Mode with Color set to ATW with defaults.  Exposure 5sec, AGC 24dB and DNR = 0.  All other settings at the camera default values.

 

Regards,

Curtis

Attached Thumbnails

  • M5 5sec 24dB  6-10-2016 2016-06-11T00_07_39.jpg
  • M11 5sec 24dB  6-10-2016 2016-06-11T00_17_37.jpg
  • M13 5sec 24dB  6-10-2016 2016-06-11T00_02_56.jpg

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#12 CA Curtis 17

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Posted 16 June 2016 - 12:07 AM

Next some more colorful objects, nebulae.

 

M16 taken with a 5sec exposure and 30dB AGC, DNR = 0, but stacked in Sharpcap for 5min to obtain a stack of 116 frames.  The stars are way overexposed but this was necessary to bring out detail in the nebula.  Note, I could not get much of anything just using the camera DNR, had to use Sharpcap.

 

M57:  First image is with in-camera stacking, no stacking in Sharpcap.  5sec, 30dB AGC , DNR =4.  Second image is also 5sec, 30dB AGC but with 1557 frames stacked in Sharpcap.  The red background in the first image is because I tried using the USER1 setting with 234B and 249R for the Color.  The Sharpcap stack was with ATW.  Clearly the ATW is better.  But the image taken without Sharpcap stacking is still pretty detailed so there is hope for those who don't want to use a computer.  Normally, I would try less focal reduction for M57 to get a bigger image, but then there would be the tradeoff of image brightness.

 

You can see the black borders in these pictures indicating how much Sharpcap had to rotate the images to stack them.

 

Regards,

Curtis

Attached Thumbnails

  • M16 5sec 30dB  4-10-2016_Stack_1136.jpg
  • M57 5sec 30dB  DNR4 4-10-2016 2016-06-11T00_39_16.jpg
  • M57 5sec 30dB  DNR4 4-10-2016_Stack_1557.jpg

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#13 CA Curtis 17

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Posted 16 June 2016 - 12:21 AM

On to some galaxies.  First M57 with and without Sharpcap stacking.

 

First one is 5sec, 36dB and DNR =6.  Certainly not as much detail as with my C9.25" but one can clearly make out both galaxies and two of the spiral arms in the larger galaxy.  Second one is also 5sec, 36dB but with DNR=0 and 1009 frames stacked in Sharpcap which shows much more detail.

 

Regards,

Curtis

Attached Thumbnails

  • M51 5sec 36dB DNR6 6-7-2016 2016-06-07T22_43_35.jpg
  • M51 5sec 36dB Stack 6-7-2016_Stack_1009.jpg

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#14 CA Curtis 17

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Posted 16 June 2016 - 12:28 AM

Finally, the galaxy M64.  As before the first image is what you could see without a computer using a 5sec exposure with AGC set to 30dB and using in-camera stacking with DNR =6.  The second image can be obtained using Sharpcap to stack 270 frames with the same 5sec and 30dB camera setting but with DNR =0.  Clearly the stacked image is smoother and shows more detail but the image using only the in-camera feature is still very good.

 

Hope these help to show, at least what someone like me can obtain using this setup.  Later this month I will get images at the GSSP in northern CA at a very dark site to compare and contrast.  Also, I will be using the ASI224MC there as well and will have to try it out in my backyard as well.

 

Best Regards,

Curtis

Attached Thumbnails

  • M64 5sec 30dB DNR6 6-10-2016 2016-06-10T23_45_29.jpg
  • M64 5sec 30dB  6-10-2016_Stack_270.jpg

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#15 alphatripleplus

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Posted 16 June 2016 - 07:01 AM

Curtis,

 

Very nice demonstration of stacking with the R2. One thing that would be helpful for those who are not familiar with analog cameras (like myself), is  the conversion from #frames in a stack to total exposure. For example, I'm pretty sure the 1557 frame stack of M57 does not translate to a total exposure of 1557 x 5sec, which would be almost 130minutes. If you could give total exposure for the R2 stacks it would help in comparing with the ASI224 when you show your 224 pics. Thanks.

 

 

Edit: I am guessing that the conversion is something like 30 non-overlapping frames/ sec for analog video, so 1557 frames would be about 1557 /30 x 5sec or  260s total exposure?


Edited by alphatripleplus, 16 June 2016 - 08:54 AM.


#16 CharlesC

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Posted 16 June 2016 - 09:27 AM

Curtis,

 

Very nice demonstration of stacking with the R2. One thing that would be helpful for those who are not familiar with analog cameras (like myself), is  the conversion from #frames in a stack to total exposure. For example, I'm pretty sure the 1557 frame stack of M57 does not translate to a total exposure of 1557 x 5sec, which would be almost 130minutes. If you could give total exposure for the R2 stacks it would help in comparing with the ASI224 when you show your 224 pics. Thanks.

 

 

Edit: I am guessing that the conversion is something like 30 non-overlapping frames/ sec for analog video, so 1557 frames would be about 1557 /30 x 5sec or  260s total exposure?

 

Its more complicated than that.  SharpCap sample rate is determined by your computers speed.  On my i3 laptop it takes about 150ms, as seen in Status tab,  to capture/stack a frame or about 7 frames per second. SharpCap doesn't know setting of exposure in camera.  SharpCap's "Total Exposure" tries to calculate actual exposure time, not true elapsed time.  Estimated elapsed time would be 1557/7 = 222seconds or 3.6 minutes.  My SharpCap python script can capture stacked pics at user specified elapsed times.


Edited by CharlesC, 16 June 2016 - 09:31 AM.

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#17 CA Curtis 17

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Posted 16 June 2016 - 09:34 AM

Errol,

 

Very good question.  I usually don't pay attention to the time it took for Sharpcap to stack the frames, but did write a few down last time.  Let me give a brief explanation.  Sharpcap tries to stack every video frame it receives.  Since the R2 is a PAL format video camera it outputs 25 frames per second (fps).  But, some frames may get lost because of the transfer speed of my USB connection, computer hardware, etc.  Each of these frames up until 5sec is the same image captured by the camera and stored it its buffer.  Only after 5 sec does the camera put out a new image and the process starts all over again.  Stacking identical images for a video camera helps to suppress random noise that gets into the video signal through connections, cables, etc.  This would not be the case for a digital camera since the output from the camera is digital not analog.  So, as you say, the total time is definitely not 1157 x 5sec.  And since not all of the 25 frames per second are actually captured by Sharpcap, it also is not 1557x 5sec /25.  The 5sec exposure really does not enter into the total time of the stacked image.  Only the fps and rate at which Sharpcap is able to capture frames, which varies, determines the time to stack.

 

I did not write down the time for most, as I said above.  But for M16 which was 1136 frames with a 5sec exposure the total time was 5min.  Going forward, I will make sure to capture the time for the stack and post it.  Thanks for pointing this out since I agree it is valuable for people to understand what is going on.

 

Regards,

Curtis


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#18 alphatripleplus

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Posted 16 June 2016 - 09:42 AM

Thanks for the clarification, Curtis and CharlesC. I remember reading somewhere in earlier posts about the issue of computing total exposure for analog cameras using SharpCap, but did not pay too much attention. In light of Curtis' forthcoming comparison with the ASI224, I'm interested now though :) .


Edited by alphatripleplus, 16 June 2016 - 09:45 AM.


#19 mclewis1

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Posted 16 June 2016 - 10:18 AM

Errol,

 

Be careful of the terminology ... you have been talking about "total exposure" which I interpret to thinking this is somewhat comparable to another camera taking a single exposure of that length. 

 

Curtis is referring to how long it takes to complete the image (total elapsed time).

 

With the type of stacking being used here a 10s exposure and stacked for say 50 times doesn't equal a single 500s exposure. It is closer in image brightness to something between a 20 and 30 second exposure (rough assumption on my part). The stacking is reducing much of the noise in the image but only making the object a bit brighter.

 

Those other threads do indeed contain some good discussion about the effect of the different types of stacking.



#20 alphatripleplus

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Posted 16 June 2016 - 11:19 AM

Mark,

 

Yes, I agree that I do need to be careful about terminology. I follow the distinction between total elapsed time in stacking with an analog camera and the "single exposure equivalent" as you explain. Thanks for the reminder, which I will try to keep in mind in this discussion. 



#21 CharlesC

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Posted 16 June 2016 - 11:20 AM

Just looked at folder of SharpCap pics taken at regular 60 second intervals using my script.  The "Total Exposure" and "Stacked Frames" vary from frame to frame, but typically are:

 

TotalExposure(s)=36.774
StackedFrames=90

 

So 90 frames per minute = one frame every 660ms 

 

Apparently even though Status tab says 150ms to acquire frame it takes 660ms to add it to stack.  Bottom line is one needs to use a stopwatch or python script to know actual elapsed time to stack a pic in SharpCap.



#22 Robrj

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Posted 16 June 2016 - 01:42 PM

Here's my light weight, portable, low cost setup:  Celestron 130 SLT, ZWO ASI185MC and my Surface 3 tablet (atom processor). 

 

VideoAstronomy Setup.jpg

 

Some things I did to the scope include replacing the dovetail mount with tube rings to give it more stability, added an Orion Accufocus as the stock 130SLT focuser is pretty crappy even for visual use, and moved the primary mirror forward.  The Accufocus makes it work much better.  I bought some extension hardware from McMaster to move the primary mirror forward.  The camera comes to focus just fine without moving the primary but moving it forward allows me to use the camera with or without a 0.5x focal reducer.

 

It's pretty light.  I can carry it out with one hand.  Tracking on it can be finicky.  Sometimes it will drift a while before settling down.  I can usually bump the arrow keys in the opposite direction to get it to stabilize.  The standarad Goto doesn't seem accurate enough for EAA.  Using the Nexstar "Precise Goto" works much better (Menu Button->Precise Goto).  It is possible to run the scope with the tablet.  I've hooked it up and driven it with Skytools 3 as a test.   But I've never tried it while observing.  I just move it manually as it's one less thing to hook up.

 

I've also attached an Orion 50mm guidescope in place of the red dot finder for widefield shots with the 185MC.  The 130SLT doesn't have a guide port.

If one were buying new, I probably wouldn't recommend this scope for someone who wants to start out with EAA.  The cost of it new plus the accufocus and the tube rings would put you close to a 6SE, which is probably much better suited.   If one already has one though, it can be made to work (I already had mine).

 

Here are some images I've taken with this setup.  Most are labeled with the gain, stack size and exposure.  Some were done with my 12" dob but they should be notated in the filename, description or a comment.

http://www.cloudynig.../6044-asi185mc/


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#23 Brollen

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Posted 18 June 2016 - 10:31 AM

Curtis

 

I recently received the R2 direct from Revolution Imaging. My interest in this approach has rapidly grown after seeing it used at Cherry Springs S.P. by someone that just purchased it earlier in the day from a vendor. He had the older R1 and was using it on a large Dob w/goto. Later that evening he was showing off M51 with video stacking - quite impressive.

 

After reading some very favorable write-ups on this PAL solution and seeing various YouTubes, I decided to take the plunge.

 

Seen here is the setup with my C90 - this was a dry run / shakeout of the integrated pieces. It worked beautifully.

 

I'm very excited about trying it out at night with my scopes and doing some image capture & stacking. As I get going and have images to show I'll post some of my work here as well.

 

Roger

 

 

Attached Thumbnails

  • R2_InitialTest_20160618_RightImage.JPG

Edited by Brollen, 18 June 2016 - 10:35 AM.

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#24 CA Curtis 17

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Posted 19 June 2016 - 07:30 PM

Rob and Roger,

 

Thanks for adding to this thread with your own versions of light weight and portable setups.  There are many options, including refractors and camera lenses as well, but I can't show them all myself, so anyone who has one of these types of setups is encouraged to post about them here.

 

Regards,

Curtis



#25 CA Curtis 17

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Posted 19 June 2016 - 07:38 PM

I promised to show the setup using the Celestron 6SE and the ZWO ASI224MC camera and here are two shots.  As you can see, the ASI fits nicely in the SCT visual back (so does the R2) and easily clears the base of the mount when pointed at the zenith.  With this camera there is only one cable to worry about, a USB cable supplied with the camera which provides power and carries the image to the computer.  A computer is require to both control the camera and view the image.  I have been using the free software, Sharpcap, to control the camera exposure and gain, capture images, as well as, stack images and adjust the light levels and manipulate the histogram.  ZWO has a deal with AstroLive which can be downloaded free to do all of the same with this camera - I just haven't had time to try yet another new thing yet.

 

I will post some images with this setup soon.  I have just recently has a chance to give it a try, but there is a bright moon out there so I want to wait until next weekend.  Plus the following week I will try both cameras with this scope at the Golden State Star Party to show what they can do at a very dark site.

 

Keep checking for additional updates.

 

Regards,

Curtis

 

 

Attached Thumbnails

  • DSCN5291.JPG
  • DSCN5292.JPG

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