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The problem with S-log on Sony A7S for wildlife video

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For me and my Sony A7S (mk1), I concluded that S-log was not useful for my purposes in most circumstances. I do mainly wildlife and nature stuff, so while I do a bit of color correction, I rarely give my footage a color grade as I usually need all the colors to look as "realistic" as possible. The main problem I had with S-log on the A7S was that while it did offer extended dynamic range, I was struggling to get the contrast and saturation back in the mid tones of the image during post, with or without various LUTs applied. I was actually struggling to get the mid tones to look anything like they do straight out of the camera with PP2 or any rec709 PP applied, which has good contrast and saturation in the mid tones, but lower DR. 


The main reason that I put this down to, was that while s-log is great for those of us wanting to apply creative color grades, and especially for people who want a lower contrast image, s-log2 and S-log3 are really meant for 10bit video files. As great as the Sony A7S is, it still outputs an 8bit signal, which means that some compromises need to be made in order to capture that extra detail in the shadows and highlights. I feel that compromise becomes apparent when you then try to put contrast back into the mid- tones and get them to look how they would if you had recorded in a rec709 profile. The 8bit image just doesn't stand up to the pushing and pulling required to get that contrast back like a 10bit or raw image would. Therefore, I concluded that the S-log profiles on the A7S would only be useful for me when I have no other choice but to shoot in super high contrast situations, and I absolutely need detail in both highlights and shadows. The rest of the time, I'm going to be exposing my rec709 image carefully, and getting my highlights under control before I start shooting.


The reason why I chose to post this here is that I see very little conversation about this problem. Most posts about s-log are from the viewpoint of people applying creative grades which, like I say, is totally valid. But, there is very little conversation about how S-log on the A7S is less useful for those of us needing to capture rich mid tones and maintain a greater accuracy in our images, and if there is any conversation about it at all, then it's being drowned out by people raving about S-log as a feature. Don't get me wrong, I love that Sony is pushing the boat out and cramming in so much to these tiny cameras for such a great price! In some ways it's a shame, because I often find myself at the mercy of the weather and other conditions, and a true high dynamic range profile would be really useful, but then again, I also understand that this is what you pay all the extra money for, when you buy a camera that can shoot 10bit, or raw video.


Anyway, I would love to hear from others in a similar situation if you have any thoughts on this. Do you shoot docs (and I don't mean those low contrast, color graded hipster docs), and have found a practical use for S-log on an 8bit video image that looks good? I would love to be proved wrong and learn how to get the best out of it. I've just purchased the A7Sii so I'll definitely keep experimenting, but I wont be using S-log2/3 for any wildlife video soon.  


Like I say, I'm not really interested in being told how great s-log is from people shooting fiction, advertising, art films etc, unless you can demonstrate that contrast and color in the midtones can be brought back to the same quality as the mid tones in a rec709 image in a side-by-side comparison. I'm looking for a sensible, open discussion, not a shouting match between fanboys/girls.



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I'm not sure I understand what the "problem" is here. Slog, as you say, is good for certain looks and shooting styles. Other situations are better served by different settings. You seem to have found the settings which produce the image you are looking for. Isn't that exactly why we have the choice? If Slog doesn't work for you, ignore it. I have no personal experience but I think log files from Canon (noted for their colour science) might change your perception of log. Would potentially be interesting for you to see what Clog offers?


I agree with the 8 bit issue (I adore the image from my Blackmagics which can - in some situations - make the Sony image look truely hideous). But surely the point is that the Sony range gives us tools (eg high iso performance, high frame rates) which excel in some - but not all - situations irrespective of that.


One minor (albeit important) point - you mention "extra money" but my BMCC (2.5k) and BMPCC were both cheaper than my A7S!



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