Luminous Landscape Forum

Equipment & Techniques => Mirrorless Cameras => Topic started by: andyptak on October 28, 2014, 04:29:50 pm

Title: Sony a7s - highest Professionally usable ISO?
Post by: andyptak on October 28, 2014, 04:29:50 pm
I'm more of a MF guy and when it comes to dusk and night shots I love my P45+ back. For an upcoming project though, I envision circumstances where a tripod might be difficult for such shots and am wondering if the Sony can cut it, handheld?

I know the kind of use - web, print etc. - will make a difference, but I'll have no control of the end use and it could go any which way. I just have to prepare the best file I can. I know all kind of high ISO's are possible, even from DSLR's, but I'm talking about quality results. Normally, I'd never go higher than 400 and even then, I'm reluctant to even go that high.

Anyone have experience? Thanks

Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Telecaster on October 28, 2014, 05:03:31 pm
Assuming professional quality == "whatever your paying clients desire," the answer then depends on the particular client, no?

My friend Bruce, who doesn't consider himself a professional, nonetheless recently did some for-pay photography for a local business. They wanted square format b&w photos with an "old-timey film look." Bruce ended up doing the project with a Hasselblad and Ilford HP5+, which he scanned and then tweaked & printed digitally. (I think the prints were 15x15".) The client loved the film grain.   :)

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: JV on October 28, 2014, 07:47:05 pm
I personally  I find the high ISO to be usable up till 51,200.

That does not necessarily mean that it is professional quality though, it also does not mean that up till 3,200 it is necessarily better than other cameras...

It does mean that you perhaps get 3-4 stops more of usable ISO than with most other cameras, for some people this will be huge, for ISO 100 only shooters this might be entirely meaningless...

Very hard to answer question, only you know which quality you and your customers have in mind.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: JV on October 28, 2014, 10:22:50 pm
An article that potentially can be interesting.  The 4 best mirrorless cameras reviewed by a professional event photographer:
http://shotkit.com/best-mirrorless-cameras-professional-photographers/

It also has a small section on the A7s:

The Sony A7s is the camera that I will set to Auto ISO without a second thought since it produces acceptable results up to 102,400 ISO. The autofocus is also surprisingly fast and reliable even in low-light conditions.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 02, 2014, 08:32:02 pm
after spending a weekend evaluating the A7s and very critically looking at the pictures, it's like this

Mood shots - up to 51000 with a fair amount of Post work can look "good" if that's what you want

Good shots can be had with some clean up up to 12500 fer sure. But some definition is lost. One could push to 25000 but it shows

Really clear below that

Of course, "Pro Useable" may mean more to less to you, but that's pretty close in my mind. Bear in mind I'm critical and you may be better in post than me but at some point the sliders just make it "different" and not "better"

Yes you can shoot at 102K but I would not publish anything but abstract at those speeds
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: andyptak on November 03, 2014, 07:14:36 am
Thanks. That's exactly the kind of first hand experience I was hoping for.

Of course, "acceptable" is in the eye of the beholder, which is why I mentioned I was a MF Phase One user, in order to give some context to my expectations.

Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 08:08:30 am
While fast, it's no threat to MF at low ISO in IQ anywhere. Great camera, but MF is MF for a reason.

Every time I que up and S2 shot (low ISO, CCD) it's like "... what is that camera...?" from whomever is over my shoulder. I never used an 800-series Nikon, maybe it gets close

Same back in the film days. There was a reason for a 503/SWC and all the gear that entailed carrying.

Nonetheless, the A7s is a powerful little beast.




Thanks. That's exactly the kind of first hand experience I was hoping for.

Of course, "acceptable" is in the eye of the beholder, which is why I mentioned I was a MF Phase One user, in order to give some context to my expectations.


Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: kers on November 03, 2014, 08:50:34 am
Is it true that is it is really silent? ( electronic shutter)
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 09:37:33 am
Is it true that is it is really silent? ( electronic shutter)

yes

all you hear is your lens stop down...

Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: jjj on November 03, 2014, 11:38:49 am
yes

all you hear is your lens stop down...
Impressive, never had a camera where that was possible.
Wish I'd had one of these when I used to do film stills. Silent and amazing high ISO quality would be perfect.
Quickly shooting scenes lit for 1/50th sec without a tripod was challenging.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: jjj on November 03, 2014, 11:40:45 am
Re professional quality, if you shoot for Alamy I gather they can reject perfect images because they may be some slight noise in the shadows on an image shot at 200 ISO in bright sunlight.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 03:10:15 pm
just re-cheacked silent shutter with M-lenses

SILENT...!!! Nothing I could hear with the EVF to my eye...

Guys, this is one hell of an overall camera...!

It still can't catch and hold a starving prostitute of an image with the Metabones IV in AF and I am now told even the dedicated E-mount AF lenses aren't that good on this body. But it can get close and close it up with a little twist if needed. but I'll be keeping my 6D for just this reason... though tempted to go to a 7D II as a complimentary body considering all the great EF-lenses I have. All the teles and zooms are AF, so would want to keep that option. But with this thing easily collecting images to 12500 that I can use, who needs another FF...? If I get the Big Res need I can always go with an A7r or it's replacement. For now peeping is not a hobby of mine. Much better to stitch and of course the 7D II will do that just fine too...

But wow... what a great addition to the litter...!
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 03, 2014, 03:31:53 pm
Impressive, never had a camera where that was possible.
Wish I'd had one of these when I used to do film stills. Silent and amazing high ISO quality would be perfect.
Quickly shooting scenes lit for 1/50th sec without a tripod was challenging.

Total exposure time is 1/30 sec in silent shutter mode, so some light sources can be problems:

http://blog.kasson.com/?p=6450

The camera's images are a little noisier in silent shutter mode:

http://blog.kasson.com/?p=6188

Also, in silent shutter mode, the a7S is a 12-bit camera.

Still and all, it's a very useful feature.

Jim

Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Telecaster on November 03, 2014, 03:33:45 pm
…I am now told even the dedicated E-mount AF lenses aren't that good on this body.

Ack, who's saying that!? The 35 & 55mm FE lenses are both very good indeed, with the 55 well into excellent territory. The 24–70mm zoom is just average, though. This is on an A7r. On the s I can't imagine them being worse.

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 03:52:57 pm
Thanks Jim, saved me looking that up...!


Total exposure time is 1/30 sec in silent shutter mode, so some light sources can be problems:

http://blog.kasson.com/?p=6450

The camera's images are a little noisier in silent shutter mode:

http://blog.kasson.com/?p=6188

Also, in silent shutter mode, the a7S is a 12-bit camera.

Still and all, it's a very useful feature.

Jim


Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 03:55:20 pm
The comment was specific to the A7s so I'm not sure it's transferrable to the A7 or the "r". It was also about zooms.

I don't want to reveal the source since he was a kind enough to be frank and deals with multiple manufacturers.

You know of him and perhaps have done business with him.



Ack, who's saying that!? The 35 & 55mm FE lenses are both very good indeed, with the 55 well into excellent territory. The 24–70mm zoom is just average, though. This is on an A7r. On the s I can't imagine them being worse.

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 04:01:52 pm
Just tried "noisy shutter" mode with M-lens

a bit louder and sharper than my M240... but not much and no double-step...
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: JV on November 03, 2014, 06:44:29 pm
Ack, who's saying that!? The 35 & 55mm FE lenses are both very good indeed, with the 55 well into excellent territory. The 24–70mm zoom is just average, though. This is on an A7r. On the s I can't imagine them being worse.

-Dave-

The comment was specific to the A7s so I'm not sure it's transferrable to the A7 or the "r". It was also about zooms.

I don't want to reveal the source since he was a kind enough to be frank and deals with multiple manufacturers.

You know of him and perhaps have done business with him.

It all depends on what you are looking for.

I can't speak for the 35mm but the 55mm is indeed a very good lens on the A7s.

It is however not a signature or characterful lens as some of the Leica lenses are, so if you are looking for a distinct special look you might be disappointed.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 03, 2014, 07:53:32 pm
I can't speak for the 35mm but the 55mm is indeed a very good lens on the A7s.

I agree. The 55 isn't jaw dropping on the a7S like it is on the a7R because of the resolution differences, but it's great.

It is however not a signature or characterful lens as some of the Leica lenses are, so if you are looking for a distinct special look you might be disappointed.

Here's a comparison of the 50 'lux and the 55 Sony, each in a receptive environment.

http://blog.kasson.com/?p=5019

There's another 55mm lens, the Otus, that has very little character, too. I think that's a feature, not a bug.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 08:19:54 pm
Well, that's a good comparison but may I inquire;

1) Isn't it pretty common to see image degradation in M-lenses in the A7r, thought perhaps to be due to the cover glass? Maybe others know much more than me... but I seem to read this not infrequently

2) I truly have no idea where you focused the -lux. It looks OOF to me regardless of crop or position. I realize that you have likely forgotten more about photography than I know, but I just don't feel comfortable with that image's focus

I'm no Leica fanboi. In fact, I love the compactness of the M's but real is real.

Was thinking of renting an OTUS 55 and comparing it to my 50-cron on the A7s

One thing for sure, there are very significant differences between the 3 items in the "A7" designation



I agree. The 55 isn't jaw dropping on the a7S like it is on the a7R because of the resolution differences, but it's great.

Here's a comparison of the 50 'lux and the 55 Sony, each in a receptive environment.

http://blog.kasson.com/?p=5019

There's another 55mm lens, the Otus, that has very little character, too. I think that's a feature, not a bug.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Telecaster on November 03, 2014, 10:55:31 pm
There's another 55mm lens, the Otus, that has very little character, too. I think that's a feature, not a bug.

I like having both options, character & lack thereof, available. That's one of the advantages of the A7 series…lots of (sometimes accidental) optical gems from the past at your disposal.

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 03, 2014, 11:16:51 pm
1) Isn't it pretty common to see image degradation in M-lenses in the A7r, thought perhaps to be due to the cover glass?

That is certainly correct, but the comparison I linked to was the 50 'lux on the M240 vs the Zony 55 on the a7. Both 24MP, both FF. The Leica body has no AA filters, tho'. The 50 was designed for no cover glass at all, not the thin M240 glass, and the Zony for exactly the cover glass it has in any of the a7 cameras.

2) I truly have no idea where you focused the -lux.

On the grape vines. The M240 LV is not as accurate as the a7 LV, but I could focus wide open at f/1.4 with the Leica lens. Because it's a RF lens, I don't expect much focus shift upon stopping down, and I haven't seen much. The Zony was focused at f/1.8. Don't forget you're looking at a 2x image blowup in both cases.

Was thinking of renting an OTUS 55 and comparing it to my 50-cron on the A7s

Here's a comparison of the 55 Otus and the 50 'lux on the a7S:

http://blog.kasson.com/?p=6357
http://blog.kasson.com/?p=6382


One thing for sure, there are very significant differences between the 3 items in the "A7" designation

Indeed.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 03, 2014, 11:43:28 pm
That is certainly correct, but the comparison I linked to was the 50 'lux on the M240 vs the Zony 55 on the a7. Both 24MP, both FF.
Jim

Now I'm truly concerned. Have shot many an image with an M240 with both my 50's, a -cron and a Noctulux and would be very disappointed seeing that image in my monitor.

Again, no insult intended but there that's a bit amazing. I must say that the LV of the M240 is no place for critical focus. The outboard EVF is is far better, especially with mag. But for a 50 I would always use the RF if possible. Nothing in my experience is as accurate and if you're shooting wide open, especially a Noctulux the light is quite low so sometimes I can't use the RF and default to the EVF. Never ever LV, even with mag though... they end up looking like that far too often

OK, checked out the OTUS vs. -lux 50.

- I have never shot with an OTUS so cannot comment completely on this particular test from that standpoint.

- the 1.4 -lux is not the sharpest of the 50mm m offerings. Better the -cron. I won't hold out for the new APO -cron since it's very rare and even if it was in stock I'd have serious considerations about plunking down N of $8K+ for that package

- Finally, it occurs that the -lux images are once again OOF. Sorry, but I expect much more from the M-glass than your test demonstrates.

Turns out I've done some head to head with the A7s and the M240 with a couple of M-lenses. Will look around and try to figure how to post to this site successfully.

No question of your integrity and knowledge, but that's just OOF until proven otherwise to me...
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 03, 2014, 11:48:25 pm
I must say that the LV of the M240 is no place for critical focus. The outboard EVF is is far better, especially with mag.

By LV, I meant with the semi-brain-dead rebranded Olympus EVF.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 04, 2014, 12:00:44 am
By LV, I meant with the semi-brain-dead rebranded Olympus EVF.

Jim

Sorry, posted over you. Yeah the Oly EVF is no Sony item... but RF is RF for a reason. When I shoot a 50 or the 90 -crons I'm amazed by how thin the true DoF is and how much difference a few mm can make
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 04, 2014, 12:34:25 am
use of the problems wit the A7s and M-adaptation is that you get NO LENS information with the Voiglander or Meatbones adapters

I have some photos, but cannot commit to them since I could be in error. I think not, but it's better for me to just shoot a new batch tomorrow in the light. I have a favorite target that seems to get to the bottom of focus, color cast and even some much loved DR

For the record, I will shoot M-lenses on both the M240 and the A7s (returned the loaner today and my B&H care package arrive almost simultaneously) So I have a brand new A7s.

I also have some great Zeiss EF- lenses that really rival anything even though they are not OTUS (21mm 2.8/ 100 mm f2 Makro-Planar) but the Metabones Mk IV for EF- to E-mount was out of stock but i may gt mine this week later

But I will be testing M-lensee on both cameras at 200 ISO wide open. Will also go to 3200 or so just to look at what happens. If you have any other requests for a side-by-side please let me know. I love this kind of stuff. No spec sheets or baloney... just look at the images and make the call
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 04, 2014, 10:52:25 am
Finally, it occurs that the -lux images are once again OOF. Sorry, but I expect much more from the M-glass than your test demonstrates.

There are a lot of variables here: demosaicing, sharpening, JPEG compressiong, etc. If the M-glass images were OOF, wouldn't there be a dramatic improvement as you stop down?

One thing I did notice about the 'lux 50 and LV focusing: it's really sensitive. Just removing your hand from the focusing ring the wrong way can cause the image to go OOF. I blame the short throw of the Leica lenses. By comparison, it's a joy to focus the Otus, with its long throw.


But I will be testing M-lensee on both cameras at 200 ISO wide open. Will also go to 3200 or so just to look at what happens. If you have any other requests for a side-by-side please let me know. I love this kind of stuff. No spec sheets or baloney... just look at the images and make the call

You can't use too stiff a tripod. Unless you always shoot wide open, I think a full aperture series would be a good idea. Remember to turn off LV before tripping the M240 shutter release (I use the self-timer) to avoid shutter shock. Use EFCS on the a7S (and the a7, if you;re going to test it). If you use an a7R, avoid shutter speeds between 1/250 and 1/15. If I'm interested in field flatness, I just focus in the middle and then look in the middle and the corners. Otherwise, I focus in the corners, too, although you can't do that with the M240. Make sure your adapter is flange-parallel. If you have tripod heads that support this move, a quick way to test is to make two exposures of a planar subject and invert the camera in between. An ISO 12233 chart makes a good target for this. You can use a mirror to make sure your camera is square to the target. That's not a bad idea in general, but it doesn't work well with natural, 3D, targets.

I apologize if you know all that already.

I'm looking forward to seeing your results.

Jim



Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Manoli on November 04, 2014, 11:25:09 am
If I'm interested in field flatness, I just focus in the middle and then look in the middle and the corners. Otherwise, I focus in the corners, too, although you can't do that with the M240.

Another practical and simple way to test for field flatness and corner resolution is to focus on a horizon line and then tilt the camera sideways so the horizon extends from lower left-hand corner to upper right-hand corner (or vice versa). First saw this in an earlier test series by another LuLa contributor - jerome_m, (if I remember correctly) so credit to him for the idea.

Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: jjj on November 04, 2014, 12:03:26 pm
Another practical and simple way to test for field flatness and corner resolution is to focus on a horizon line and then tilt the camera sideways so the horizon extends from lower left-hand corner to upper right-hand corner (or vice versa). First saw this in an earlier test series by another LuLa contributor - jerome_m, (if I remember correctly) so credit to him for the idea.
Neat and simple.   :)
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 04, 2014, 02:24:14 pm
- Finally, it occurs that the -lux images are once again OOF. Sorry, but I expect much more from the M-glass than your test demonstrates.

I went back to the M240//lux Ps stack and zoomed in on the center of the f/5.6 image. I see pixel-level details, which wouldn't happen if the image were OOF.

(http://www.kasson.com/ll/m240lux.PNG)

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Telecaster on November 04, 2014, 02:27:50 pm
Yeah the Oly EVF is no Sony item... but RF is RF for a reason. When I shoot a 50 or the 90 -crons I'm amazed by how thin the true DoF is and how much difference a few mm can make

Just to note: the EVF in Oly's E-M1 (made by Epson?) is in a different league to the M240's "Visoflex" finder. IMO it's at least as good as the Sony's, better contrast-wise in bright light. Leica gets major demerits from me on both the EVF and the 240's inability to move the magnified point-of-focus around in the finder. Agreed on RF focusing, at least for lenses 50mm & under.

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 04, 2014, 03:05:36 pm
Just to note: the EVF in Oly's E-M1 (made by Epson?) is in a different league to the M240's "Visoflex" finder. IMO it's at least as good as the Sony's, better contrast-wise in bright light. Leica gets major demerits from me on both the EVF and the 240's inability to move the magnified point-of-focus around in the finder.

Right you are. And the EVF picked by Leica wasn't even the best Oly shoe-mount EVF available at the time.

Agreed on RF focusing, at least for lenses 50mm & under.

I hear you , but my eyes are too old to love the RF experience. I do find the M240 RF an improvement over the M8 and M9 ones, though.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: JV on November 04, 2014, 07:25:31 pm
Leica gets major demerits from me on both the EVF and the 240's inability to move the magnified point-of-focus around in the finder. Agreed on RF focusing, at least for lenses 50mm & under.

Add the EVF of the Fuji X-T1 also to the list of much better EVF...

With the next M Leica really needs to step up and improve big time on the EVF and on the focusing aids other than RF.

You already see a pattern right now where people complement their M8 or M9 with a Sony.  They don't contemplate the CMOS M.  That trend is only going to get stronger IMO.

You see the same with other models like the X Typ 113.  Sexy camera but really, no built-in viewfinder?  The Fuji X100S has two... and costs half of the price...

IMO it is really simple.  If Sony delivers on the lenses and improves on the bodies with the next generation they will take most of the mirrorless market and make serious inroads into the DSLR market.  
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 08, 2014, 07:59:44 am
Ack, who's saying that!? The 35 & 55mm FE lenses are both very good indeed, with the 55 well into excellent territory. The 24–70mm zoom is just average, though. This is on an A7r. On the s I can't imagine them being worse.

-Dave-

Hey Dave. Had time to form my own opinion on this with the Sony 55mm 1.8/24-70 4.0/70-200 4.0

They are fine for all but the most demanding circumstances

My 6d with a 50mm 1.4/24-105 f4/70-200 4.0 is that the Canon is significantly but perhaps not so importantly... faster in AF acquisition. BY a noticeable amount. Again though, not many situations will use that difference.

Amazing what the 6D does with so many "inferior" parts and systems. Really is. That's another very underrated camera. Some feel the 5D3 somewhat superior. Construction... yes. Output... no.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 08, 2014, 04:06:54 pm
Hey Dave. Had time to form my own opinion on this with the Sony 55mm 1.8/24-70 4.0/70-200 4.0

They are fine for all but the most demanding circumstances.

I haven't tested the 24-70, but in my experience the 55 and the 70-200 are in different area codes. The 70-200 is about the same, and maybe a bit better than my current-rev Nikon 70-200 f/2.8. My Zony 55 is amazing. I've only tested the one sample, though.

By the way, on the subject of multiple sample testing, I wish I could do it, but it's just not practical for me. I do have two copies of the Sigma 50mm ART lens, and they turn in materially identical optical performance.

Jim

PS 1000!
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Telecaster on November 08, 2014, 04:29:08 pm
My 6d with a 50mm 1.4/24-105 f4/70-200 4.0 is that the Canon is significantly but perhaps not so importantly... faster in AF acquisition. BY a noticeable amount. Again though, not many situations will use that difference.

Yes, the Sonys aren't the speediest cameras AF-wise. And PD-AF systems do prioritize speed over accuracy. (D-SLR dig required to meet monthly quota.   :D ) I'll be much happier with the FE lineup when I have 28 & 85mm lenses to complement the 55 & 35mms. Until then it's mostly manual focus for me.

-Dave-
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: andyptak on November 08, 2014, 06:28:17 pm
A lot of interesting information here, but to come back to my initial question - ya'll remember that don't you?

After a bit of testing and some guesswork, I think I'd have to push the ISO to at least 3200. Can the 7s cut it and produce decent work at that range? Obviously it would have to be cleaned up in post, but is that even possible with this camera? Thanks.
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: Jim Kasson on November 08, 2014, 06:31:07 pm
A lot of interesting information here, but to come back to my initial question - ya'll remember that don't you?

After a bit of testing and some guesswork, I think I'd have to push the ISO to at least 3200. Can the 7s cut it and produce decent work at that range? Obviously it would have to be cleaned up in post, but is that even possible with this camera? Thanks.

IMHO: Yes! Better than the D3s at that ISO, if you've used that camera.

Jim
Title: Re: Sony a7s - highest Professionally usable ISO?
Post by: allegretto on November 08, 2014, 08:24:45 pm
A lot of interesting information here, but to come back to my initial question - ya'll remember that don't you?

After a bit of testing and some guesswork, I think I'd have to push the ISO to at least 3200. Can the 7s cut it and produce decent work at that range? Obviously it would have to be cleaned up in post, but is that even possible with this camera? Thanks.

 Oh yes, I recall

at 3200 you need do nothing. 6400 too . Not till 12800 do you have to start lifting in PP. A good 4 -stops on your MF

Further, the files are just... pretty. Big pixels do that. My D4 made files that killed the 7100 in spite of the latter's denser pack. it wasn't noise either. It killed at 1600 too. Very sweet. Even ate my Fuji X-Pro which I liked the look of.

What I like about Sensorgen.info is that they give you very complete ISO/DR files as some but they also give you e- for noise and sat capacity. Note the A7s just blitzes the field and I think that may contribute to what I "see'