A7s sample footage

pask74 said:
Just looking for a plain explanation for not-so-techies like myself here ;-)
Does this mean that the A7s' DR is the same in all modes but that using the flatter S-Log profile provides more latitude?
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PP7 has SLog2 Gamma which provides the most dynamic range from the α7s. PP7 also has Color Mode set to S-gamut, which can have issues with too much green. Color Mode can be changed to Cinema, Pro, Rec709, or any other Color Mode, which will not change the dynamic range: maximum dynamic range is provided by the Slog2 Gamma curve.
 
Aha. So, basically, PP7 is an SLog2 preset that has several flavours in terms of colour modes? If so, is there a reason to favour one over another (except from aesthetic choices)?

jcs said:
PP7 has SLog2 Gamma which provides the most dynamic range from the α7s. PP7 also has Color Mode set to S-gamut, which can have issues with too much green. Color Mode can be changed to Cinema, Pro, Rec709, or any other Color Mode, which will not change the dynamic range: maximum dynamic range is provided by the Slog2 Gamma curve.
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Sgamut may come out green and purple but graded, it's nicely balanced and more neutral. If you want lots of color, make sure to add a bit more saturation to the profile. Probably not needed if you choose rec709 which is really punchy in the reds already at 0.
 
pask74 said:
Aha. So, basically, PP7 is an SLog2 preset that has several flavours in terms of colour modes? If so, is there a reason to favour one over another (except from aesthetic choices)?
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As far as DR, Slog2 does not yield higher absolute DR, but the flatter curve makes for increased highlight and shadow detail (at the expense of mid-tone detail). But, DR will "appear" to be higher in high-key scenes or scenes with high contrast lighting. Absolute DR in this camera is as high as any DSLR or C-series Canon as far as I can tell, and with the flat curve it's awesome, but difficult to work with since exposure needs to be dead-on due to the 8-bit mapping.* As for color, in all 8-bit recordings, colors are being sampled and re-mapped into an 8-bit space, so Sony offers different mapping algorithms, or "modes". These do not effect DR. Which mode is chosen is a matter of taste and style, but I think most people will pick one that offers the least amount of grading to the final result.

And PP7 is just a preset using the S-log gamma curve and the S-gammut color mode. The camera stores 7 PPs internally, all are customizable with any combination of gamma curve and color mode (along with other adjustments).
 
Slog2 is a flatter curve but to say the A7s has as much DR as any other Canon right now is like saying the only difference between an Alexa's 14-15 stops of DR and a C100 is a curve. Not the case. The A7s sensor can clearly produce more usable stops of DR and Slog2 allows you to tap it's full range. I mean, that's already been tested to produce more range than a fair amount of the competition but we all know the quality of that image isn't reflected in those scores. The A7s is a great low light cam and gives you the Sony look, cine gammas and makes a smaller companion to their larger lineup. It's great for what it is at the price it is considering the rest of their models. I agree that you have be considerate of the 8bit codec but it's also not yesterday's 8bit either. You have some decent flexibility if you overexpose. Lots of data still present,
 
It's not been easy to sort through the information presented here but I've learned enough to decide to order an A7S, so thank you for those making strong contributions here.

I'll be testing against an F55 next week with similar modes and curious to see the comparison. My ultimate interest is seeing whether I can intercut footage with Alexa, and how much it can be pushed and pulled.

For what it's worth, I do feel that the 8-bit debate is overstated by many. I shot the a season of TV that way a couple years ago (F3 with s-log recording to external XDCAM) and we did heavy grading and never saw any issues. And as cyork says, it's not yesterday's 8 bit to boot.
 
cyork said:
Slog2 is a flatter curve but to say the A7s has as much DR as any other Canon right now is like saying the only difference between an Alexa's 14-15 stops of DR and a C100 is a curve. Not the case. The A7s sensor can clearly produce more usable stops of DR and Slog2 allows you to tap it's full range. I mean, that's already been tested to produce more range than a fair amount of the competition but we all know the quality of that image isn't reflected in those scores. The A7s is a great low light cam and gives you the Sony look, cine gammas and makes a smaller companion to their larger lineup. It's great for what it is at the price it is considering the rest of their models. I agree that you have be considerate of the 8bit codec but it's also not yesterday's 8bit either. You have some decent flexibility if you overexpose. Lots of data still present,
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I haven't read all of these pages but I can say from owning both that the A7s has at least the same usable DR of my c300 and probably a stop or two over that. In 8 bit. the C300 is a perfect example of the good 8 bits. Very easy to work with in post. I find the A7s holds up well too, but the 420 hurts the extremes. Can't wait for the shogun!
 
CharlesPapert said:
It's not been easy to sort through the information presented here but I've learned enough to decide to order an A7S, so thank you for those making strong contributions here.

I'll be testing against an F55 next week with similar modes and curious to see the comparison. My ultimate interest is seeing whether I can intercut footage with Alexa, and how much it can be pushed and pulled.

For what it's worth, I do feel that the 8-bit debate is overstated by many. I shot the a season of TV that way a couple years ago (F3 with s-log recording to external XDCAM) and we did heavy grading and never saw any issues. And as cyork says, it's not yesterday's 8 bit to boot.
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Prior to getting the A7s I was shooting exclusively with the 5D MK3 ML raw and my observation so far is that you can do a lot with the 8bit S-log in post and I'm not really missing raw much. The final graded A7s image is slightly softer. I think the only real difference is the usable exposure range is a bit narrower, and of course the colours are different but you can get them fairly close in post. As far as usable dynamic range goes I think the A7s has the edge on the MK3 raw off the sensor BUT you can recover a bit more from the raw file in most without degrading the image so it probably evens out. It certainly leaves every other 8bit DSLR for dead.
 
NeedCreative said:
I haven't read all of these pages but I can say from owning both that the A7s has at least the same usable DR of my c300 and probably a stop or two over that. In 8 bit. the C300 is a perfect example of the good 8 bits. Very easy to work with in post. I find the A7s holds up well too, but the 420 hurts the extremes. Can't wait for the shogun!
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The only thing I've noticed between shooting XAVC S and prores 422HQ is some macroblocking in fast motion. Resolution and pushing the grade wise they were both pretty much on par, the XAVC S actually looked a bit better in some shots. I'm still interested in the Shogun for a good 4k to 10bit luma 2k conversion.
 
I don't care for the grade of the miller video either. a lot of footage I've been seeing have really been imo abusing the allotted dynamic range and has caused footage to look very thin. I think why canon footage looks so appealing from the gate is because of the pop in its color. I know these things are subjective and these grades may work for some but I really like a more poppy grade.
 
Have to say I agree. Most of the footaage I see from this camera looks 'thin' color-wise. Perhaps it was a mistake to try to capture 8 bit log footage.
 
I've been playing with the A7s and we'll be putting together a technical analysis of the A7s and GH4 soon (dynamic range, noise, resolution, skin tones etc).
So far I'm not as happy as I expected with the results. It's not bad, but maybe not up to all the hype :(

 
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Funny I felt the same about that miller video but didn't say anything asthoughI was in the minainority. I love most of his work but that particular lut I felt like I liked the raw s log better half the time.
 
Yeah, I can see Miller's LUT being good if you remove the milky hipsterness out of it and bring back SOMETHING to an actual black. Lots of great stuff available now with LUTS already released.
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