CCD or Sony a7s?

[vertigo262]

I have been researching, 1) weather to go mono and color. Whole different issue. But I have been researching the Sony A7s.

I am now wondering if my next investment should be towards a ccd like atik or qhy, or a sony a7s.

I haven't found many telescope images, the ones I've seen are spectacular in the times it takes to record them. of course on larger scopes.

also, the night shots with just a lens of the milky way seems pretty amazing in exposures like 10 seconds.

I noticed one company is converting them to full spectrum. This brings in a lot of confusion weather investing in a ccd, or getting a Sony A7s might get better results for the price range.

I don't see much control software as APT looks like they are attempting to work with sony for something. But A good tethering program I think would temporarily solve that.

Any thoughts, sample images would be helpfull.

[kalasinman]

It might be helpful for you to list what equipment you currently have and what you are trying to accomplish.

It could be argues that the current state of the art for imaging in DSLRs is the old Nikon d5100 and D7000. Once debayered by someone capable, given the Nikonhacker firmware, they are pretty unbeatable. Others may have more pixels, but that's often a minus. If you doubt the potential, take a look here

http://stargazerslounge.com/topic/236643-nikon-d5100-monotec-narrow-bands/

He also does the debayering. You could spend more and get less. FYI the read noise of a D5100 with the Nikonhacker firmware has been measured at 1.7 e- at room temperature compare that to most CCDs.

I may do the wide spectrum with IR/UV cut baader filter mod to my D5100. I do have the stuff to do it here, but on non-dominant Ha targets I like the native color balance of the non-modded camera. When I mod it, I'll have to spend time in processing getting a better (less red) color balance on many targets. Not a clear choice.

If I had the money for the full narrow band kit, I'd be looking at a cooled CCD, not trying to mod a DSLR into something it wasn't designed to be. Not saying others shouldn't, or that their results aren't quite impressive. Just my thoughts.

[vertigo262]

Have you seen what the a7s can do? just a single picture in a few seconds can get the mily way. and what I've seen it do on the few articles I've seen in a short time is amazing. although, it always looks better until you go out and try to do it yourself. But the exposure times were extremely short, and iso 3200 was noise free.

I am mostly doing nebulas.

I am considering narrowband, but not sure, especially if something like the a7s can get better. Which I don't know if it can.

I have explore scientific Ed 127

advanced vx

orion guider

This canera is also full frame. and I thing ISO goes up to 402,000 

They are doing pitch black hand held video and it looks clean at like 50 - 100,000 iso

I saw some realtime tests on a 14" SCT and hyperstar and you could see the gasses in real time. I'm have a feeling narrow band on a mono camera has better results. But if this can get close, in a 10th of the time. it's a possibility

[kalasinman]

As to the Sony A7s, I can see why it interests you. Flange to sensor distance might require some creative spacers for focus, I doubt you'll find a way to Ha mod it, shutter control might be an issue which could make it unusable with the popular camera control software such as BYEOS. For me, $2500 for a non standard camera body is a lot. If you want to take on the project, it could really yield some great images.

[dph1nm]

But the exposure times were extremely short, and iso 3200 was noise free.

Even if you eliminate read and dark noise, then at the end of the day you are going to be shot noise limited in astro work, so when you reach that level the camera doesn't really matter (obviously higher QE is better in that regard, but most DSLRs have similarish QE)

NigelM

[vertigo262]

I would think if you went with an a7s, you'd be going color. And I can't afford to toy around. Although from the few images and videos I've seen online it seems spectacular. APT is working on trying to get it integrated, who knows if it will.

I really would like to just try one out. But I think in the back of my mind, I will be going CCD and Mono, narrowband. But after seeing some of the images, I start to think. Why waste the time when it looks like it might be able to do better and way faster. 

But that is something you never know until you do it yourself with the equipment. I was all set to move towards mono and narrowband. Then I saw what people were doing with the a7s.

Sony seems to be the leader in sensors as far as low light and sensetivity, I have a feeling a lot of people will be using the a7s and newer versions for astro photography.

You could wing it with tethering software, but it wouldn't be as nice. 

but, it definitely got me thinking. I want to see what more people do with it and their setups.

After watching the 14 inch hyperstar live viewing nebula gases in realtime. That was extremely amazing. although he did have a 1.9 aperture and a 14 inch scope.

[bwana]

I have been using a Sony A7R and A7S for astrophotography since they came on the market.  I've had both cameras modded to full spectrum by Life Pixel.  Hutech also sells modded A7 series cameras.

Prior to acquiring the Sony cameras I had a full spectrum Canon 60D and two OSC CCD's.  All three of these cameras have now been sold.  I still have a mono ATIK 428Ex for narrowband imaging... which I haven't used since modding the Sony A7R.

I used both Sony cameras for astro/nightscape photography (primarily with a Hutech HEUIB-II filter but also with Ha and narrowband filters), IR photography (with various IR bandpass filters) and daytime photography (with a Kolari Color Correction filter).

My analysis of the various cameras shows the A7R to be about 2-3 stops better than the Canon 60D and the A7S to be about 2-3 stops better than the A7R...  The A7S is actually quite phenomenal.  I normally use it at ISO 3200-6400 for astro-imaging; however, I've pushed it to ISO 12800 with good results and to ISO 25600 with acceptable results.  I've used it at ISO 51200 but wouldn't go as far as recommending it at this ISO, although video shot at ISO 51200-102400 is acceptable, i.e.: Aurora Borealis, Milky Way, moonlit nightscapes, etc..  I use the A7R in the ISO 1600-3200 range.

Since I've acquired the Sony cameras I have shot all my imaging sessions unguided simply because I seldom have to go beyond 1-2 minutes exposure time.  I haven't shot or used dark subs since purchasing the Canon 60D.  I also do not shoot flats or bias subs.  I do all gradient removal in PixInsight or Lightroom.

I use a minimalist approach to imaging.  I use EQ6Pro, Az-EQ6 or Celestron AVX mounts with a fair bit of effort put into polar alignment.  I use wired remote timers to control my cameras and capture all subs to camera memory, i.e.: no hassle of a computer/laptop for imaging!.  I use Bahtinov masks to focus all my camera lenses and telescopes.  I've found them to be far easier, faster and more accurate than software to get a good focus.  Also, the A7S and a camera lens will autofocus on stars.

I've shot a lot of astro sessions and done a fair bit of testing with the two Sony cameras.  If you're interested, a few of the results (good, bad and truly ugly) can be found at:

Misty Valley Ranch Observatory

I have no problem recommending the Sony A7S for OSC astrophotography.  If you're looking at the A7R, I would recommend you also take a good look at the Canon 6D.  The A7R and 6D are in the same league.

bwa

[vertigo262]

I will take a look. what software are you using with the a7s to capture. and how do you think it would compare to the atik 11000, or to narrowband?

[AnakChan]

I chose a CentralDS Astro A7s for my introductory Astro camera. I wanted cooling in addition to the A7s sensitivity. The total cost for me was $2730 with my own A7s (bought 2nd hand for $1442 & CDS mod $1288).

CDS took 4 weeks to mod & return the camera, which I received yesterday. So I've not had a chance to try it out yet.

The reason for my choice of this option is because I get the benefit of a full frame sensitive sensor & cooling. Admittedly I am lucky to be in Japan where I can pick up 2nd hand cameras at cheap prices in mint condition.

[AnakChan]

I forgot to add (I have no edit rights to my previous post), I also chose the DSLR route over the CCD as for me as carrying a notebook/laptop around for imaging is somewhat less practical. I live in Tokyo and have to travel out to get dark skies. My portable powersupply is probably enough to run my mount & camera but I'd rather not further add a notebook load strain on it.

[bwana]

I forgot to add (I have no edit rights to my previous post), I also chose the DSLR route over the CCD as for me as carrying a notebook/laptop around for imaging is somewhat less practical. I live in Tokyo and have to travel out to get dark skies. My portable powersupply is probably enough to run my mount & camera but I'd rather not further add a notebook load strain on it.

I don't have a problem with power for a laptop, i.e.: I run out of an observatory or out of my garage; both have power.  I simply don't like the hassle of using a laptop when I don't really require one.  

My A7S is not cooled other than by the cool/cold weather of central Alberta, Canada.  I've seen very little difference in image quality operating at +20C vs. -20C ambient.

The Misty Valley Ranch is about 150 km from the nearest serious source of light pollution so I'm relatively lucky that way.  I wouldn't want to try imaging from the center of Tokyo or any other major city !

bwa

[bwana]

I will take a look. what software are you using with the a7s to capture. and how do you think it would compare to the atik 11000, or to narrowband?

Not too sure who you're asking regarding software?  If me, I no longer use a computer or software for capture.  I find astro-imaging much easier and more fun w/o the hassle of a computer.

Not familiar with an ATIK 11000 but I do have a mono ATIK 428Ex.  It does a better job of narrowband imaging than an A7S but you're talking a totally different level of exposure times and processing.  With my ATIK 428Ex I'm shooting probably 15x5-15 min. Luminance, Ha, Sii & Oiii subs or LRGB subs, aligning/stacking the individual sessions, combining, blending, etc., ad nauseum.  With the A7S I'm shooting 50x30 sec. (maybe 30-40x60 sec.) subs with relatively simply processing in PixInsight and Lightroom.  Two different worlds of astrophotography.  I've been in both worlds with three different OSC CCD's, two mono CCD's, four unmodded DSLR's and three full spectrum DSLR/mirrorless cameras.  I'm now quite happy doing 30-45 min. imaging sessions and getting a reasonable result.  If I'm not happy with the results, I sometimes break down and shoot longer subs, or shoot another session or two and stack the results.

Everyone has their own approach to a astro/nightscape photography...  Mine is (sorta) the lazy man's approach! 

bwa

[vertigo262]

Let me ask it another way. If for example astro magazine came to you (name made up of course), and said. We want you to take a picture of this nebula for the cover of our magazine, would you use a mono ccd and narrowband, or the a7s?

[AnakChan]

I don't have a problem with power for a laptop, i.e.: I run out of an observatory or out of my garage; both have power.  I simply don't like the hassle of using a laptop when I don't really require one.  

My A7S is not cooled other than by the cool/cold weather of central Alberta, Canada.  I've seen very little difference in image quality operating at +20C vs. -20C ambient.

The Misty Valley Ranch is about 150 km from the nearest serious source of light pollution so I'm relatively lucky that way.  I wouldn't want to try imaging from the center of Tokyo or any other major city !

bwa

That's interesting. I thought the cooling will help. However the recent DPReview of the A7s doesn't sound too promising. It's a pity I had sent my A7s already by then as from reading the review, I think I would have been better off sending the A7ii instead (higher res, same noise levels as A7s, still benefit from silent shutter on the newer Alphas for B exposures).

[bwana]

Let me ask it another way. If for example astro magazine came to you (name made up of course), and said. We want you to take a picture of this nebula for the cover of our magazine, would you use a mono ccd and narrowband, or the a7s?

If they wanted a Luminance, Ha, Oiii, Sii narrowband, I'd use a mono CCD and filters.  If they simply wanted an LRGB image, I'd use the A7S.

[bwana]

That's interesting. I thought the cooling will help. However the recent DPReview of the A7s doesn't sound too promising. It's a pity I had sent my A7s already by then as from reading the review, I think I would have been better off sending the A7ii instead (higher res, same noise levels as A7s, still benefit from silent shutter on the newer Alphas for B exposures).

From our testing of noise levels on the A7S and A7 II, there is NO comparison.  The A7S is 2-3 stops better.  The A7 II compares nicely with the A7R, the older A7 and the Canon 6D.

As for the silent shutter, I don't use it at all on the A7S because when using the silent shutter the bit level of captured images is downgraded.  Also, the silent shutter does not work with Bulb mode and a few other features of the camera.

bwa

[vertigo262]

You missed the point of my question. if you were going for total quality and perfection. What path would you choose?

[vertigo262]

also, I think you mentioned doing Ha on the a7s? how are you doing that if it's not mono? I've seen someone else mention they did an ha on it as well. So I was curious how they did it

[kalasinman]

You missed the point of my question. if you were going for total quality and perfection. What path would you choose?

Olly is arguably one of the best imagers alive. If you really are serious about TOTAL perfection, copying him wouldn't put you far wrong. Examples :  http://stargazerslounge.com/topic/237263-the-400-hour-image/

Just to be clear, this image made by Ollypenrice.

[vertigo262]

well, no need to copy anyone . Besides, I'm a one man show on a budget. But I will try to create some wonderful imagery. I just need to know the path I am taking. Everything kind of says narrowband.

But it's a lot of work. But I think their is really no way around that in astro photography. and it almost seems, like I think Olly said somewhere. Trying to make osc work, with all the messing around probably comes about the same amount of time as doing it right.

Although, when I see what the a7s can do. I wonder if you can get some quality for a fraction of the time. But honestly, I doubt it

[vertigo262]

Besides, my own styles have always made the world mad and jealous since I was 10 years old

[kalasinman]

Yes no need to copy the work, but the studious, pragmatic, results oriented approach is what I was referring to. The mounts that produce this level of work are all on the order of $7,000 or more. The software is rarely the free kind. Olly writes equipment reviews for Astronomy Now magazine, and thus is exposed to a wide range of gear. He has a Mesu 200 and a full frame Atik camera.

[vertigo262]

I've seen his work and posts. There's no doubt he does it right, and amazing work. I'm sure he has a lifetime of knowledge about it. I can't afford that kind of equipment, but I believe I can get great pictures if done right and put in the effort. I'm not competing with anyone, never have, so non of that bothers me.

I think right now my bottleneck is a camera and good exposures. and the question of, do I just go narrowband which solves most the issues although takes a lot longer but you don't have to worry about trying to make rgb or osc work, as opposed to exerting your energy to making it happen, instead of fudging ok results.

All the best photos I've seen seem to be narrowband. But every now and then I see some osc or rgb that impress the [removed word] out of me.

I saw a short exposure heart nebula, had more data then any one i've seen with the a7s. blew me away.

That is when I started to question. well, if he can do that quickly.

But the reality I am sure is. It's never as easy as it appears. even with good equipment. And why narrowband just makes sense.

better for light pollution, higher resolution, more sensitive in monochrome. your efforts are in the combining and taking pictures. whereas most my effort in rgb has been. Now I got something, how do I make it look presentable.

You know the outcome better, just have to focus on doing the process.

 but like I said. then some yabbo gets some mind blowing pictures in a couple of hours and you say. that looks easier

but then again. The things that take no climbing, we loose interest in anyways. because then it's too easy.

I think Olly might be right when he said that. narrowband probably doesn't take much longer when you have to try to fudge everything else to make it as good.

But I still want to try out a a7s, because what I've seen it can do from video to astro photography is pretty damn cool! 

[bwana]

You missed the point of my question. if you were going for total quality and perfection. What path would you choose?

There is no such thing as "total quality and perfection" in astro-imaging; every image is a compromise, even Hubble images.  I've already answered your question.  Astro-photography is roughly 10% data collection and 90% processing, just like most other types of photography.  It isn't necessarily the equipment that makes a great photo.  It is the person behind the camera.

[bwana]

also, I think you mentioned doing Ha on the a7s? how are you doing that if it's not mono? I've seen someone else mention they did an ha on it as well. So I was curious how they did it

I do narrowband imaging with both the A7R and A7S, and previously with my Canon 60D.  One does not require a mono CCD to mount narrowband filters and capture subs.  A full spectrum camera "sees" the same spectrum width as a mono camera, it is simply split by the Bayer filter to three channels.  It is really not much different than using a mono camera or shooting IR with a modified DSLR/mirrorless camera.

The 1st nine images in Sony A7S & AT8RC - 2014Oct30+ were shot with a Baader Ha filter on Astro-Tech 8" RC using an A7S.  They are not the best of results due to cloud moving into the area later in the evening.

bwa