Amazon A7s info claim A7s has 15.3 stops of DR!

that number is in the Sony promotional material
we still don't know if it's for video, or only for RAW stills, and, if for video, how much of that will be usable
 
Yeah that seems crazy but if it's true it will be amazing. Then again I'd hope that if they gave it SLOG2, it should be able to hold a solid 13-14stops like the other SLOG2 cameras do.

Just imagine, maybe they had to clip off a couple of stops to make it the DR fit into a standard SLOG2 container... I hope they didnt clip any of it off!
 
I wouldn't expect more than 12 stops in an a 50mb/s 8bit container like Canon has done with their Clog on C300. I don't think its possible to cram 15 stops into 8bit. Its still 8bit 4K coming out of the HDMI to ext recorder also which limits things a little.

Keep a healthy perspective. Sony isn't going to rival their top of the line cams with a $2.5K mirrorless.
 
I believe it's a completely new sensor, not used in any product before the a7s.

Also: in theory, you can fit 255 stops of DR in 8-bit and you're still representing all of them. It will look like s*%t, but you can do it if you want. Whether they put all the DR from the sensor into the 8-bit video or not, it's a choice full of trade-offs, not something determined by technical issues.
 
To be honest i will a camera which could capture great image with excellent DR, sharpness and color science than another one which need too extra module to record a 10bit image but which need massive color grading to compensate what the cam should done right first.

I want to have the most of the cinematography right in camera, then i just want a cam which feel transparent but i could trust to capture the moment as it is.
So far, despite i really want to love the Gh4 as it's cheap and available, i can't convinced myself yet to push the "buy" button hoping the A7s while having his own weakpoint would give more "wow" results. Now im open to change my mind for any option

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Samuel H said:
Also: in theory, you can fit 255 stops of DR in 8-bit and you're still representing all of them. It will look like s*%t, but you can do it if you want. Whether they put all the DR from the sensor into the 8-bit video or not, it's a choice full of trade-offs, not something determined by technical issues.
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Very true
 
Yeah, realized it was Sony's official info on the Amazon site after posting. Ooops.

And also, in my video centric world I didn't stop and think about raw for photos...

However... even if it gets 13 stops for video, that combined with the better codec (50mps XAVC S vs 24mps AVCHD) it could possibly in many situations beat the FS700 which I currently use as main camera. And that in this tiny form factor at less than half the price. I'm hoping to buy one as a b-cam/mobile cam.

8 bit is a curse on both the FS700 and the A7s though :(
 
As long as the A7s delivers "only" 8bit through the HDMi, any log-alike profiles won't make that much sense anyway.
Extra flat and desaturated profiles need delogging or heavy grading which means much more tonality than 8bit to look good.

As far as I know, the GH-4 is the only camera in it's range, giving true 10bit HD over HDMi.

I expect the A7s to behave very similar to other 35mm-sensor DSLRs but with 2-3 steps better lowlight capability. If dynamic range is your biggest concern, take one of the BM cams and have fun grading.
If you want it the quick way, produce consumer codec footage without log-profiles but with almost deliverable in camera looks.

Sony will never give the ability of a 10bit High DR machine to one of their cheap photo camera, they wanna still sell in the FS700/F5/F35 class...

I checked the FS700 with the CG Odyssey and 10bit 4k-HD ProRes footage last week - amazing stuff!
 
Well, for the A7s the biggest draw to me is the low light capabilities as I operate almost exclusively in dark environments. But dynamic range is, I believe, the most important feature for great picture. But, as said, it should be in a 10bit format.

The Odyssey is a bit out of my price range unfortunately. At around $3500 for 7Q + codec license + expensive media, I just can't swing it. I need a b-cam more as it is now. And I'm hoping to sell my EA50 to fund the A7s. Or I could go with a 7Q but then I'd only have one camera and a debt.

I'm hoping Atomos will support FS700 2K/4K ProRes at some point with the Shogun.
 
Erik Wittbusch said:
As long as the A7s delivers "only" 8bit through the HDMi, any log-alike profiles won't make that much sense anyway.
Extra flat and desaturated profiles need delogging or heavy grading which means much more tonality than 8bit to look good.
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There was a lot of SLog2 footage used in the Sony launch videos which looked fine to me even through the veil of YouTube encoding.

No one is disputing that RAW of the BMCC is able to be graded in post more but in reality how often is an 8 bit image moved so much that it crumbles and how much of that crumbling is due not to the 8 bit image but the underlying compression?

The 10 bit out of the GH4 is a bit moot given its noise and lack of dynamic range. Personally I'd rather have the clean output and high dynamic range from the A7s in 8 bits over the GH4's any day of the week.

It's a pretty good bet that the sensor in the A7s will end up in a slew of products including replacements for FS100/700/F5 etc and given the 4K Video camera Z100 has 10bit compressed recording I'd expect that to come too and probably sooner rather than later. Whenever you buy camera equipment you run the risk of something coming out in 6 months that surpasses it but at $2500 you should've made a your ROI by then.
 
Nirv said:
The 10 bit out of the GH4 is a bit moot given its noise and lack of dynamic range. Personally I'd rather have the clean output and high dynamic range from the A7s in 8 bits over the GH4's any day of the week.
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The GH4 isn't noisy below ISO 1600 really. At least not from what I have seen and I personally don't shoot in situations much beyond that so for me personally that is not the appeal of the A7s. For me its all about DR and we still have to see how much they can cram into 8bit slog. We know that 8bit Slog wasn't great on the FS700 so only once we see non sponsored samples of footage and real DR tests will be know where this camera stands above the 9-10 stop GH4 DR. My guess is 12-13 stops.
 
RatLabProductions said:
The GH4 isn't noisy below ISO 1600 really. At least not from what I have seen and I personally don't shoot in situations much beyond that so for me personally that is not the appeal of the A7s. For me its all about DR and we still have to see how much they can cram into 8bit slog. We know that 8bit Slog wasn't great on the FS700 so only once we see non sponsored samples of footage and real DR tests will be know where this camera stands above the 9-10 stop GH4 DR. My guess is 12-13 stops.
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Download some of the GH4 footage and take a look at how riddled with noise the darker tones of the image are even in bright sunlight.

Im not overly concerned by the exact DR but rather more interested to see if Sony manages to ensure their cine gamma curves give a pleasing roll off to white.
 
I have to agree. Even at 200 ISO on my GH4 (1080p recorded 10bit to Ninja Blade) when exposing to protect highlights, I run into ugly noise when grading, long before I see any of the advantages of recording 10bit!

All the 8bit to 10bit comparisons I've shot on the GH4 look practically identical...

Im really hoping that the dynamic range on the A7s allows me to shoot much more in the way I shoot with the c300, where I don't have to worry too much about slamming into the highlights, because they roll-off in a visually pleasing way.
 
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Erik Wittbusch said:
As long as the A7s delivers "only" 8bit through the HDMi, any log-alike profiles won't make that much sense anyway.
Extra flat and desaturated profiles need delogging or heavy grading which means much more tonality than 8bit to look good.
Click to expand...

8 bit images contain more than enough color information to be de-logged and graded. May not have the same latitude as higher bit depth images, but as long as your smart about your exposures and color balance you shouldn't have a problem.
 
These 15 stops might be only in RAW using highlight recovery. This is used when one of the channels clip first, usually green. Then the highlights can be reconstructed from the unclipped channels. There is such a difference in the sensitivity of the channels that it's just part of the RAW process. In some situations you can gain another stop of range. The Slog2 output wouldn't be using this. Slog2 can hold just about 14 stops - so it might fill it nicely.

But as has been mentioned Spreading those in 255 (or less) values is difficult. The Slog2 off the FS700 isn't true Slog, it has an S curve applied on top to roll off the highlights and make slightly better use of the range - i'd expect this to do the same..

It's a shame though, all this colour detail in 8 bit. Such a shame. However taking the 8 bit out at 4K and downsampling would create an effective image with >8 bits.

I hope it comes out on time though, my stills camera is buggered and i'm on the waiting list. I love the fact it has a silent shutter, that's IMHO one of the biggest deals for me

cheers
Paul
 
paulcurtis said:
The Slog2 off the FS700 isn't true Slog, it has an S curve applied on top to roll off the highlights and make slightly better use of the range - i'd expect this to do the same..
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Nice. That makes it slightly more difficult to grade but it would help a lot on the a7s.

BTW Amazon changed the expected delivery date of the a7s, but not in the usual way: from July 8th to July 1st.
 
Samuel H said:
Nice. That makes it slightly more difficult to grade but it would help a lot on the a7s.

BTW Amazon changed the expected delivery date of the a7s, but not in the usual way: from July 8th to July 1st.
Click to expand...

I think some Sony Stores are showing 30th June too. So you never know, perhaps Sony are on schedule (sadly i remember the delays with the FS700 so perhaps this is a different department)

cheers
Paul
 
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