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Sony A7S - Viable for EAA?

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#1 schwim

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Posted 22 June 2015 - 02:27 PM

I've been doing the EAA thing for about 6 months with a MC Xtreme2 which I control and view with my computer. I've been amazed at the things I've been able to see with this set up. Yet, I'm left feeling like the analog output and low resolution are just.... lacking.  I took interest in the A7S as a potential "cross over" camera - one where I could still do the things I've been doing with the MC-X2 (hopefully better, actually), and have a device that can get me started in astrophotography. I've seen at least one individual on NSN using the A7S as an EAA camera that can also do AP. I've been tracking the AP forum and see the A7S as viable for my needs on the AP side.

 

My question for this forum is specific to EAA application of the A7S. Have you done it? If so, how? How does it compare to the dedicated EAA cameras that are out there? What software are you using to control and broadcast on NSN? Are there other cameras I should consider in lieu of the A7S? Ideally I'd like something that I can get dual use out of.

 

As far as exposures, I tend to think of them as integrations. I don't need a "real time" view. I'd argue that I'm not even getting that with my MC, as I have to wait for the integration to complete to see the object.

 

Any advice and/or help is appreciated!

- Greg



#2 coinboy1

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Posted 22 June 2015 - 02:56 PM

I think the A7s is a perfect outreach/EAA camera because of its super sensitivity. Even 1/4 sec video mode exposures @ ISO ~200,000 yields some impressive images of the night sky. Check out youtube videos of it, it is super impressive. I also thought that mallincams are a bit outdated technology. The DSLR market is always on top when it comes with Research and Development. I think DSLRs are the future of EAA IMHO.


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#3 schwim

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Posted 22 June 2015 - 03:22 PM

I think the A7s is a perfect outreach/EAA camera because of its super sensitivity. Even 1/4 sec video mode exposures @ ISO ~200,000 yields some impressive images of the night sky. Check out youtube videos of it, it is super impressive. I also thought that mallincams are a bit outdated technology. The DSLR market is always on top when it comes with Research and Development. I think DSLRs are the future of EAA IMHO.

 

So you are using one for EAA? What is your set up? I'm hoping to control/display on my laptop.



#4 Dom543

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Posted 22 June 2015 - 04:03 PM

Unfortunately, Sony A7S users were chased away from this forum.

Their threads were transferred to the DSLR Imaging and Processing forum, where they quickly expired. What we are doing in EAA is considered gross overexposure and overall nonsense from point of view of an astrophotography forum. So it is not feasible to post EAA images or experience on the DSLR forum.

To answer the question in the title of this thread, yes it is probably very viable. It's just that there is no place on CN for people with that camera to share their EAA experiences or post their unprocessed real-time captures.

Clear Skies!
--Dom
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#5 chasing photons

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Posted 22 June 2015 - 04:40 PM

Although the ¼ second video mode of the Sony A7S is impressive for show, it is quite noisy.  Where it really shines is in short, still exposures in the 30 second range.  What is needed is good software to get these short and very impressive images to a laptop or tablet and offer on the fly processing. 

 

It sounds like the A7SII will be out soon and who knows what improvements we will see.  Maybe using a Back Side Illuminated sensor for even more sensitivity?  A more astro friendly SDK to help programmers produce near real time observing apps?  It would be great if Sony patterned it more towards an astro specific camera like the offerings from Canon and Nikon.  Maybe we will also see a Sony A7SIIa astro camera.

 

I personally hope that all of the camera manufacturers will enter the small astro camera market with their own offerings.  I would like to see a camera like the A7S in a smaller size sensor, either APS-C or Micro 4/3, in the 10 - 12 MP resolution range with slightly smaller pixels.  This would lower the camera price and make it a better match with smaller aperture, shorter focal length and lower cost optical tube assemblies.


Edited by chasing photons, 22 June 2015 - 04:40 PM.


#6 CHAPSKINS

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Posted 22 June 2015 - 04:42 PM

Yeah, I've got an A7s. I haven't been able to use it so far with my telescopes other than a few tests with video via a crummy Canon lens as the weather has been poor. What I have seen so far has really impressed me.

I plan to use it on a hyperStsr setup which should give some great widefield views. When I get a chance and shoot some live DSO stuff, I'll post it up here. I've not had the camera modified as yet, and I'm still debating wether or not to do so :shrug:

I was in the same boat as you as I too have a Mallincam X2 and was not totally happy with the results, so, I went for the Sony number. I've got to say, I've taken some cracking daytime pictures with f it - can't be down to skill as I'm all out on that account - naw, I can't wait to put it through its paces when it comes to using it for astronomy :)



#7 dwkdnvr

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Posted 22 June 2015 - 04:58 PM

 

 

I personally hope that all of the camera manufacturers will enter the small astro camera market with their own offerings.  I would like to see a camera like the A7S in a smaller size sensor, either APS-C or Micro 4/3, in the 10 - 12 MP resolution range with slightly smaller pixels.  This would lower the camera price and make it a better match with smaller aperture, shorter focal length and lower cost optical tube assemblies.

I doubt we'll see much in the way of Astro-specific functionality from the 'mainstream' manufacturers, but I guess never say never. the market just seems awfully tiny, and most are already hurting due to the overall decline in the standalone camera market.

 

I have an Olympus E-M5 MkII (m43) which I'm intending to try out in an EAA style manner at some point - hopefully soon. It provides USB tethering including image transfer to the laptop (jpeg only unfortunately, which might undermine the whole idea). It's not in the same league as the A7S but is surprisingly decent at high ISO, and I do wonder whether with 2x2 pseudo-binning (turning it into a 4MP sensor with ~7.5 micron pixels) it might not be reasonably successful when paired with a stacker like Astrotoaster.  I'm certainly holding off on buying a more upscale color camera until I can try it out.

 

I'd love to try an A7S, but the price point is just a bit rich for my blood at this point. If an A7SII is announced with internal 4k recording (or some other killer feature that would drive existing owners to upgrade), I'd definitely look at picking up a used A7S if the price were right.



#8 CHAPSKINS

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Posted 22 June 2015 - 05:02 PM

Although the ¼ second video mode of the Sony A7S is impressive for show, it is quite noisy.  Where it really shines is in short, still exposures in the 30 second range.  What is needed is good software to get these short and very impressive images to a laptop or tablet and offer on the fly processing. 

 

It sounds like the A7SII will be out soon and who knows what improvements we will see.  Maybe using a Back Side Illuminated sensor for even more sensitivity?  A more astro friendly SDK to help programmers produce near real time observing apps?  It would be great if Sony patterned it more towards an astro specific camera like the offerings from Canon and Nikon.  Maybe we will also see a Sony A7SIIa astro camera.

 

I personally hope that all of the camera manufacturers will enter the small astro camera market with their own offerings.  I would like to see a camera like the A7S in a smaller size sensor, either APS-C or Micro 4/3, in the 10 - 12 MP resolution range with slightly smaller pixels.  This would lower the camera price and make it a better match with smaller aperture, shorter focal length and lower cost optical tube assemblies.

 

 

I was reading the posts on Sony's public SDK development site and it doesn't look like they are ready to open it up that much apart for WiFi remote applications and what-not.

 

From what I've been reading, astro stuff just isn't on their horizon. On a more positive note, there is a site out there working on opening up Sony's firmware - possibly a dev increasing video times? How long that will take is anyone's guess.

 

The only software that I found for the A7s that was remotely usable - there must be other software out there for this camera - is Capture One...it's ok. It's an in-depth application and feature rich and takes some getting used to, but it does do live view, just like Canons application.



#9 chasing photons

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Posted 22 June 2015 - 05:24 PM

 

Although the ¼ second video mode of the Sony A7S is impressive for show, it is quite noisy.  Where it really shines is in short, still exposures in the 30 second range.  What is needed is good software to get these short and very impressive images to a laptop or tablet and offer on the fly processing. 

 

It sounds like the A7SII will be out soon and who knows what improvements we will see.  Maybe using a Back Side Illuminated sensor for even more sensitivity?  A more astro friendly SDK to help programmers produce near real time observing apps?  It would be great if Sony patterned it more towards an astro specific camera like the offerings from Canon and Nikon.  Maybe we will also see a Sony A7SIIa astro camera.

 

I personally hope that all of the camera manufacturers will enter the small astro camera market with their own offerings.  I would like to see a camera like the A7S in a smaller size sensor, either APS-C or Micro 4/3, in the 10 - 12 MP resolution range with slightly smaller pixels.  This would lower the camera price and make it a better match with smaller aperture, shorter focal length and lower cost optical tube assemblies.

 

 

I was reading the posts on Sony's public SDK development site and it doesn't look like they are ready to open it up that much apart for WiFi remote applications and what-not.

 

From what I've been reading, astro stuff just isn't on their horizon. On a more positive note, there is a site out there working on opening up Sony's firmware - possibly a dev increasing video times? How long that will take is anyone's guess.

 

The only software that I found for the A7s that was remotely usable - there must be other software out there for this camera - is Capture One...it's ok. It's an in-depth application and feature rich and takes some getting used to, but it does do live view, just like Canons application.

 

 

 

Hmmmm...  It will be interesting to see what you can do with your A7S and Capture One when the weather improves.



#10 Relativist

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Posted 22 June 2015 - 05:39 PM

The A7s isn't the issue, it's the software support. That said, it is possible to use RCC & Astrotoaster/DSS. It's the same workflow that I would use for my a5100.

#11 schwim

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Posted 23 June 2015 - 12:00 AM

Unfortunately, Sony A7S users were chased away from this forum.
 

 

Is there a high priest of EAA that decides what cameras can be talked about?  :p

 

In all seriousness, if we can use the A7S, or any other camera for EAA is this not the right forum for it? For the record should any moderators need to know, I'm asking about the A7S specifically in an EAA application only here.

 

 

 


 

The only software that I found for the A7s that was remotely usable - there must be other software out there for this camera - is Capture One...it's ok. It's an in-depth application and feature rich and takes some getting used to, but it does do live view, just like Canons application.

 

 

 

Hmmmm...  It will be interesting to see what you can do with your A7S and Capture One when the weather improves.

 

 

I agree. I'm not afraid of complicated software, unless it's Lotus Notes. That one was scary. Whew....

 

The A7s isn't the issue, it's the software support. That said, it is possible to use RCC & Astrotoaster/DSS. It's the same workflow that I would use for my a5100.

 

Are you doing (or have you done) this? Mind sharing your set up and experiences?

 

Thanks all for the responses!


Edited by schwim, 23 June 2015 - 12:01 AM.


#12 Relativist

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Posted 23 June 2015 - 02:02 AM

I have not used the Astrotoaster/DSS part of the equation because I'm on a Mac and it was crashing on me via parallels. That said, I did get it to open the files I had prepared during my testing. The way Astrotoaster/DSS works is by monitoring a folder and pre-processing prior to viewing. There is software called Remote Camera Control (RCC) that I have used to control the exposures in the camera and once taken RCC will place the file in a designated folder (the same one Astrotoaster/DSS monitors).

 

Ideally, if you try this hopefully you'll be using a decent windows machine.



#13 ccs_hello

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Posted 23 June 2015 - 07:15 AM

IMHO I think if we don't overly emphasize the astrophtography aspect of the A7s and post lots of heavily processed beautiful astro images, we will be okay to stay in this forum.

 

After all, A7s has (almost) all desirable attributes of a "fast" imaging system:

1. very large pixel size

2. extremely low noise characteristics, in this generation, it's almost "ISO-less" 

3. when ISO is 2000 or higher, a high charge-to-voltage conversion value kicks in, this is like high gain without the pre-AMP noise injected

4. these recent SONY mirrorless cams are leaning toward WiFi-tether as opposed to USB tether,

    with multiple schemes of remote controlling the cam, it is still manageable

 

The A7s price when compare with the overall astro-dedicated imaging systems pricing scheme, in relative term, is quite reasonable.

 

Of course A7s does have a few drawbacks.  The biggest one is for continuous shooting (movie mode) without mechanical shutter kicks in, is only 0.25s.

However we creative souls can either use high ISO (noisy, but up to EAA's low S/N threshold), live-stacking viewing in movie mode, or

live-stacking in continuous-shot (individual file transfer) mode.

 

As for me, I am waiting for A7S-II, A7S-III coming out, so the "old" model will have a lower price tag.

If I have this cam, I will use this forum as the conduit to show its EAA benefit.

 

Clear Skies!

 

ccs_hello



#14 chasing photons

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Posted 23 June 2015 - 09:28 AM

I keep going back to member jdbastro's work with the unmodded Sony A7S because he achieves really nice, straight out of the camera, single jpeg images in 30 seconds or less with NO post processing.  He does have nice glass and a dark site, but you still have to be in awe of his results with this camera.  He also does a lot of work with image intensifiers, but I enjoy the stuff from just the A7S.  Here is a link with many single image posts and it also includes a link to one of his image albums.

 

http://www.cloudynig...-from-sony-a7s/

 

The only problem with past posts in the EAA forum involving the Sony A7S had to do with the posting of stacked images with significant post processing.  As long as this is explained with the posted image, I have no problem with it.  But then someone not familiar with astro imaging might expect to get such results straight from the camera in near real time observing mode.

 

I am all for cameras like the Sony A7S for use in EAA.  I hope we see a flood of similar cameras from all of the mirrorless and dslr manufacturers.


Edited by chasing photons, 23 June 2015 - 09:28 AM.


#15 schwim

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Posted 23 June 2015 - 10:38 AM

Ideally, if you try this hopefully you'll be using a decent windows machine.

 

Nope - I use Mac and I'm finding it to be an unfortunate experience getting things to work. So many tools are windows only, or just work better on windows. I can't even control my mount well. I'm running windows in a VM, but may just give in to buying a dedicated PC.



#16 schwim

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Posted 23 June 2015 - 11:25 AM

Here is a link with many single image posts and it also includes a link to one of his image albums.

 

http://www.cloudynig...-from-sony-a7s/

 

 

Images like this are what I'm after, presuming I can do so with a "near real time" viewing experience.

 

Regarding the camera's automation capabilities, I'm wondering how the RCC software works. If it's doing things via IP over Wifi, it should be easy to sniff the commands out and reverse engineer the command set. From there, I can probably script something together to at least control the camera at some level.

 

Hmm... quiet weekend coming up, kids are with the ex, and Best Buy has the A7S in stock.... I wonder what the balance on my credit card is. :)



#17 DonBoy

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Posted 23 June 2015 - 02:27 PM

My concern with the A7S is that the sensor's pixels are 8.4u x 8.4u and it doesn't appear that it's sensitivity is much different than ICX828/829 cameras.   If I were using the same scope at the same FR there would be no resolution gain compared to cameras like those using  ICX828/829 because of the similar pixel size.  Those cameras that use these sensors like the Xterminator, SR-DS, LSX2 all provide the same resolution for image size and are cheaper and easier to use and exposures are just as short or shorter.  

 

Maybe I'm missing something here.  If the A7S was more sensitive that these other cameras then one could use the same scope at a higher FR; thus longer FL, and end up with higher resolution for the same length of exposure as these other cameras.  

 

Where I think the A7S would shine would be in video mode if the frame rate could be changed from 1/4sec to something greater like 1sec or more.



#18 schwim

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Posted 23 June 2015 - 03:39 PM

My concern with the A7S is that the sensor's pixels are 8.4u x 8.4u and it doesn't appear that it's sensitivity is much different than ICX828/829 cameras.   If I were using the same scope at the same FR there would be no resolution gain compared to cameras like those using  ICX828/829 because of the similar pixel size.  Those cameras that use these sensors like the Xterminator, SR-DS, LSX2 all provide the same resolution for image size and are cheaper and easier to use and exposures are just as short or shorter.  

 

Maybe I'm missing something here.  If the A7S was more sensitive that these other cameras then one could use the same scope at a higher FR; thus longer FL, and end up with higher resolution for the same length of exposure as these other cameras.  

 

Where I think the A7S would shine would be in video mode if the frame rate could be changed from 1/4sec to something greater like 1sec or more.

 

How would this be measured in practicality?



#19 Relativist

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Posted 23 June 2015 - 05:31 PM

That's a good question, looking at what people have posted so far I think we might be able to have a feel by now.

#20 mclewis1

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Posted 23 June 2015 - 05:35 PM

My concern with the A7S is that the sensor's pixels are 8.4u x 8.4u and it doesn't appear that it's sensitivity is much different than ICX828/829 cameras.   If I were using the same scope at the same FR there would be no resolution gain compared to cameras like those using  ICX828/829 because of the similar pixel size.  Those cameras that use these sensors like the Xterminator, SR-DS, LSX2 all provide the same resolution for image size and are cheaper and easier to use and exposures are just as short or shorter.  

 

Maybe I'm missing something here.  If the A7S was more sensitive that these other cameras then one could use the same scope at a higher FR; thus longer FL, and end up with higher resolution for the same length of exposure as these other cameras.  

 

Where I think the A7S would shine would be in video mode if the frame rate could be changed from 1/4sec to something greater like 1sec or more.

Don,

 

Yes the resolution will be similar and that means we won't be able to "blow up" (to use the old photography term) the images any more than those from other cameras. But do we need to do that? I mean are we running up against the resolution limits in EAA viewing? Certainly we are on solar system objects, but is it also a problem for DSOs?

 

That bigger sensor gets us a lovely big fov. We should have sensitivity in roughly the same range as the smaller sensors (although I think the 82X series sensors still have the absolute edge here). What we need (and has been said over and over again) is suitable software ... something like MiloSlick or LodeStar Live so we can work with the camera in a "live" viewing setup and still have some in line processing capabilities. 

 

Yeah, if the one in the A7S or similar sensors was even more sensitive we could get away with slower f ratios and the corresponding longer focal lengths, and then we'll really start pushing on that resolution issue.

 

Lower prices would be nice too  :undecided:



#21 DonBoy

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Posted 23 June 2015 - 05:56 PM

 

How would this be measured in practicality?

schwim,

 

That's a tough question, and I don't know how to answer that with the proper scientific way of evaluating cameras. This is always a problem when comparing cameras.  I rely on my 8 years at EAA and 99% of that has been live broadcasting.  

 

The way I end up comparing cameras is to use them over several evenings with the same setup and then look at the captures and the exposure settings I used to obtain them.  I also take a look at other individuals postings to see how they compare with setup and exposure.  Not having an opportunity to use the A7S I must then rely on the images that are published or viewed live on NSN and compare them to my images and other veteran EAA imagers. 

 

I've seen one EAA operator who has done live imaging on NSN using the A7S and a MallinCam Xterminator (ICX828) and several other cameras and this gives me even more of a gauge on performance capabilities. 

 

I recently had a two night test of an Atik 414 color camera and I ran it with my typical scope setup and FR.   As expected the images had more resolution and greater depth of field for very similar exposure times as my ICX418 camera.  The single frame images were noisier but the 5 stacked results were very pleasing.  Here are some Atik images (no post processing). 

https://www.flickr.c...157654256664726

 

 

 

 

 



#22 schwim

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Posted 23 June 2015 - 06:11 PM

 

 

How would this be measured in practicality?

schwim,

 

That's a tough question, and I don't know how to answer that with the proper scientific way of evaluating cameras. This is always a problem when comparing cameras.  I rely on my 8 years at EAA and 99% of that has been live broadcasting.  

 

The way I end up comparing cameras is to use them over several evenings with the same setup and then look at the captures and the exposure settings I used to obtain them.  I also take a look at other individuals postings to see how they compare with setup and exposure.  Not having an opportunity to use the A7S I must then rely on the images that are published or viewed live on NSN and compare them to my images and other veteran EAA imagers. 

 

I've seen one EAA operator who has done live imaging on NSN using the A7S and a MallinCam Xterminator (ICX828) and several other cameras and this gives me even more of a gauge on performance capabilities. 

 

I recently had a two night test of an Atik 414 color camera and I ran it with my typical scope setup and FR.   As expected the images had more resolution and greater depth of field for very similar exposure times as my ICX418 camera.  The single frame images were noisier but the 5 stacked results were very pleasing.  Here are some Atik images (no post processing). 

https://www.flickr.c...157654256664726

 

 

Indeed. I think the true test is going to be a side-by-side comparison that looks something like comparing the result of equivalent "integration" times between any two given cameras with their "best" possible settings for the object. Subjectivity will always rule, but I suspect one camera may just be plain better.

 

Then there's the control aspect. I think the A7S is way behind in this regard, for now.

 

By the way, those pics look great!



#23 DonBoy

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Posted 23 June 2015 - 06:42 PM

 

Yes the resolution will be similar and that means we won't be able to "blow up" (to use the old photography term) the images any more than those from other cameras. But do we need to do that? I mean are we running up against the resolution limits in EAA viewing? Certainly we are on solar system objects, but is it also a problem for DSOs?

 

That bigger sensor gets us a lovely big fov. We should have sensitivity in roughly the same range as the smaller sensors (although I think the 82X series sensors still have the absolute edge here). What we need (and has been said over and over again) is suitable software ... something like MiloSlick or LodeStar Live so we can work with the camera in a "live" viewing setup and still have some in line processing capabilities.

 

Yeah, if the one in the A7S or similar sensors was even more sensitive we could get away with slower f ratios and the corresponding longer focal lengths, and then we'll really start pushing on that resolution issue.

 

Lower prices would be nice too  :undecided:

Mark,

 

For streaming on the web using NSN I believe we are currently doing just fine with the 8u pixel cameras.  But for me I prefer more resolution on my side of the streaming.  Wider FOV on NSN will not benefit from more resolution but from a larger sensor.  And this adds more stringent requirements for a focal reducer.  A sensor like the ICX825 in a larger format would satisfy both more FOV and more resolution with it's slightly smaller sensitive pixels (6.45um).

 

And a promising possibility to atleast fit the higher resolution bill could be the IMX224 currently being developed by ZWO , but it will need stacking I believe. 

 

We're in exciting times.

 


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#24 Don Rudny

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Posted 23 June 2015 - 07:30 PM

Hi All,

 

I find this type of discussion very interesting.  I don't know what the answer is or even if there is one, but it appears to me to come down to resolution for a particular image scale.  As Don pointed out the pixel size of the A7s is large similar to the Sony 829 sensor..  The sensor is much larger at full frame.  So, unless we use much longer optics to get the same image scale, the resolution cannot be appreciated.  Longer optics will generally be slower (and more expensive), so exposure times will be longer, again for the same image scale.  To address the A7s in particular and to show my point, I looked at the images in the linked A7s image album above.  The image of M57 was taken with a Mewlon 250 at F12 and cropped down to an APSC size.  Exposure was 30 seconds.  To compare, the attached capture of M57 was recently made by me with my M8 at native F10 with my Lodestar X2c.  Exposure was 15 seconds.  The A7s image has a FOV of 24.1' and mine is 11.1'.  To get equal image scale, the A7s still needs to be cropped more even at 3000mm.  Putting aside the color differences, when I enlarge the A7s image to equal mine, I don't see the resolution benefit, even with the longer, arguably better, optics.

 

If I'm off base on this, please let me know.  As Don said,  these are exciting times in EAA.  

image.jpg



#25 Relativist

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Posted 23 June 2015 - 07:33 PM

Don't forget longer optics could also be had by larger aperture. Maybe a simple 1920x1080 crop of the center with slightly larger optics will be possible, instead of requiring the full sensor illumination if one cannot afford the larger optics.

What a nice problem to have :-)


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