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A7s Grading


Tim Naylor

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Yes the secret to using s-log2 at least with default PP7 is not the gamma curve it is the s-gamut. You must convert the s-gamut colorspace to sRGB if you want to get reliable colors. Sure a lot of the time you can just add contrast and get something that is close but it is just a hack with some nasty surprises. This is why so many have trouble with s-log2 they just bring it and do some curve adjustments and add saturation which is totally wrong. I find that with default settings s-log2 when converted properly almost has too much saturation, there is no way I would ever increase the saturation in camera as there is plenty there.

 

This conversion can be done with a lut or with a matrix transform as posted previously. The problem with luts as I understand it is that the shot must be exposed and white balanced properly to get a reliable conversion with a 3dlut. The Impulz luts are calibrated assuming you have exposed normally. If you shot 2 stops over to help with noise in the shadows these luts will no longer convert properly. Using a 1D lut for s-log conversion and a color matrix for s-gamut to sRGB doesn't appear to have this issue and is my preferred method at this point.

 

I have a sample workflow with adobe products that I posted before showing how to do this. I have recently found that my 1D lut is a little off of the formula supplied by sony. It has a little less contrast in the highlights which I actually prefer but I may have another go at it to see if I can fix that. It would by nice if there was a way to control color using expressions in Adobe. Any know if that is possible?

 

Here is the post I was talking about.

 

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Hey guys, I threw a sample video together for you...   pass: jockjams   It's a compilation of some paid work I've done with the A7s.     I'm really against shooting s-log2 with this camera.

Hello all,   I've been a DP most of my career, a situation where I shoot footage and then the manipulation of the footage is literally out of my hands. With movies, I sit in on the grades and superv

"Get ready for this" - I remember liking that song as a little boy... Didn't expect to hear that song today :)     I like a lot of what I've seen from the A7S. My main nitpick with that camera is t

Thanks everybody for such informative posts. I'll be shooting a job this weekend with the A7s and will be applying quite a bit of what I got out of this thread. But still keep the info flying.  I especially found the Espionage Films Tests most encouraging. They got some excellent tones out of the camera. Not perfect but more than acceptable.

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Hey guys, I threw a sample video together for you...

 

pass: jockjams

 

It's a compilation of some paid work I've done with the A7s.  

 

I'm really against shooting s-log2 with this camera.  I've never been able to get anything but weird results from it. Maybe I'm just not a good enough colorist, but I haven't seen many other people get good color from it, either.

 

My current favorite shooting mode is the creative style Autumn Leaves with contrast -3, sat 0, sharpness -3.  I set wb manually to compensate for a7s's tint problems.  Then I grade in FCP X.

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Yeah that all looked very nice Brandon. I saw a bit of the give-away A7S magenta in one or two of the midday shots, but here it adds up to nothing more than the negligible quirks of most other cameras ...

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"Get ready for this" - I remember liking that song as a little boy... Didn't expect to hear that song today :)

 

 

I like a lot of what I've seen from the A7S. My main nitpick with that camera is the Sony color science.

 

When I compare the Sony colors to the Nikon colors that I'm so used to - there is something odd with the color science of Sony Alpha cameras. I've struggled with trying to get same color and same white balance out of my NEX-5R as I do with the stills from D800 or the near ancient D200. Since the struggle is there with raw, movie mode and jpegs, it's some other processing characteristic of the cameras that is the issue.

 

 

With raw stills I've found that no matter what I do, there's some kind of cast that just isn't there on my Nikons (not even on the old D200). Colors seem off compared to what I saw when I captured the still and compared to the Nikons not mattering how I adjust the white balance in Lightroom. If I shoot a portrait on D800, I find in most light situations that I can tweak it and say that is very close to what I saw with my eyes at the scene. In good light / low ISO, D200 is usually not that far from what a D800 can achieve colorwise, I can get fairly close to natural colors.

 

What I find with the Nex, is that I either have a magenta cast for the whole face, or I lose the reddish colors that you often find in shadow areas of a face as well as the reds for lips. Instead, the whole face has a uniform yellow/brownish skin color and a lot of skin color nuances are lost. If I want skin colors close to natural skin color, I'll have to resort to a lot more post-work than just adjusting a few sliders in Lightroom.

 

Also, in dramatic/high contrast scenes, containing higher dynamic range: you just can't adjust white balance and expect the shot to look good all the way from deepest shadows to brightest highlights. You'll have to pick best white balance for midtones + highlights, or best white balance for midtones + shadows.

 

I assume Nikon does some processing to create a better color / white balance output for the full dynamic range in their processing that Sony does not.

 

In Brandon's video, as well as in many stills and videos from Sony alpha cameras, I can recognize these color tendencies that I've struggled with: getting skin tones natural looking in a variation of light conditions, getting nature scenes in dramatic/high contrast light to not have extra color casts.

 

 

Don't take me wrong on this one. I like the A7S and what it can do. But I'd really love it if it came with Nikon colors out of the box. My ideal camera at the moment would be some kind of mirrorless blend of D750 and A7S, although the A7S as-is comes close.

 

 

EDIT: Oh, and I forgot why I got interested in commenting in the first place - great shots Brandon! I really like the camera movements, brings such a natural organic feel to the footage. Is it mostly handheld? Monopod? Are you using stabilisation in post? I need to learn :)

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Brandon, you have some nice comps there.

 

However, the colors on the A7s are just way off on nearly every shot. Not sure what the problem is.

 

If you were in fact attempting to shoot 'out of the box' without S-Log 2, to do a sort of comparison against the 5D3/Nikon D750/D810 to match colors,  than this is yet another test that clearly shows the dominance of Canon/Nikon colors science  VS Sony.

 

It seems the best colors out of the A7s would be using S-Log 2 and doing major color correction. Out of the box with this cam just doesn't work.

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"Get ready for this" - I remember liking that song as a little boy... Didn't expect to hear that song today :)

 

 

I like a lot of what I've seen from the A7S. My main nitpick with that camera is the Sony color science.

 

When I compare the Sony colors to the Nikon colors that I'm so used to - there is something odd with the color science of Sony Alpha cameras. I've struggled with trying to get same color and same white balance out of my NEX-5R as I do with the stills from D800 or the near ancient D200. Since the struggle is there with raw, movie mode and jpegs, it's some other processing characteristic of the cameras that is the issue.

 

 

With raw stills I've found that no matter what I do, there's some kind of cast that just isn't there on my Nikons (not even on the old D200). Colors seem off compared to what I saw when I captured the still and compared to the Nikons not mattering how I adjust the white balance in Lightroom. If I shoot a portrait on D800, I find in most light situations that I can tweak it and say that is very close to what I saw with my eyes at the scene. In good light / low ISO, D200 is usually not that far from what a D800 can achieve colorwise, I can get fairly close to natural colors.

 

What I find with the Nex, is that I either have a magenta cast for the whole face, or I lose the reddish colors that you often find in shadow areas of a face as well as the reds for lips. Instead, the whole face has a uniform yellow/brownish skin color and a lot of skin color nuances are lost. If I want skin colors close to natural skin color, I'll have to resort to a lot more post-work than just adjusting a few sliders in Lightroom.

 

Also, in dramatic/high contrast scenes, containing higher dynamic range: you just can't adjust white balance and expect the shot to look good all the way from deepest shadows to brightest highlights. You'll have to pick best white balance for midtones + highlights, or best white balance for midtones + shadows.

 

I assume Nikon does some processing to create a better color / white balance output for the full dynamic range in their processing that Sony does not.

 

In Brandon's video, as well as in many stills and videos from Sony alpha cameras, I can recognize these color tendencies that I've struggled with: getting skin tones natural looking in a variation of light conditions, getting nature scenes in dramatic/high contrast light to not have extra color casts.

 

 

Don't take me wrong on this one. I like the A7S and what it can do. But I'd really love it if it came with Nikon colors out of the box. My ideal camera at the moment would be some kind of mirrorless blend of D750 and A7S, although the A7S as-is comes close.

 

 

EDIT: Oh, and I forgot why I got interested in commenting in the first place - great shots Brandon! I really like the camera movements, brings such a natural organic feel to the footage. Is it mostly handheld? Monopod? Are you using stabilisation in post? I need to learn :)

 

It is a bit of a lost cause because intangible's things like colour science cannot be measured. So it does not look as sexy on the spec sheet and the hype machine cannot work enough. I have been playing and grading some shots done by my cousin on my D7100 (not really a shooter, more of a special effect and editing coming out of University) when I was shooting beach wedding in very harsh light. If I knew how to upload photos (Every time I try it tells me the image has to be less than 70K, which is ridiculously low to show some 1080p jpeg) I would post some frame grabs. I mean they are much better of what I have seen here and I did not have to lots of correction. Just some saturation and contrast to taste. It is not as if I needed some PHD in colour science to get some proper skin tone in very harsh lighting.

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"Get ready for this" - I remember liking that song as a little boy... Didn't expect to hear that song today :)

 

 

I like a lot of what I've seen from the A7S. My main nitpick with that camera is the Sony color science.

 

When I compare the Sony colors to the Nikon colors that I'm so used to - there is something odd with the color science of Sony Alpha cameras. I've struggled with trying to get same color and same white balance out of my NEX-5R as I do with the stills from D800 or the near ancient D200. Since the struggle is there with raw, movie mode and jpegs, it's some other processing characteristic of the cameras that is the issue.

 

 

With raw stills I've found that no matter what I do, there's some kind of cast that just isn't there on my Nikons (not even on the old D200). Colors seem off compared to what I saw when I captured the still and compared to the Nikons not mattering how I adjust the white balance in Lightroom. If I shoot a portrait on D800, I find in most light situations that I can tweak it and say that is very close to what I saw with my eyes at the scene. In good light / low ISO, D200 is usually not that far from what a D800 can achieve colorwise, I can get fairly close to natural colors.

 

What I find with the Nex, is that I either have a magenta cast for the whole face, or I lose the reddish colors that you often find in shadow areas of a face as well as the reds for lips. Instead, the whole face has a uniform yellow/brownish skin color and a lot of skin color nuances are lost. If I want skin colors close to natural skin color, I'll have to resort to a lot more post-work than just adjusting a few sliders in Lightroom.

 

Also, in dramatic/high contrast scenes, containing higher dynamic range: you just can't adjust white balance and expect the shot to look good all the way from deepest shadows to brightest highlights. You'll have to pick best white balance for midtones + highlights, or best white balance for midtones + shadows.

 

I assume Nikon does some processing to create a better color / white balance output for the full dynamic range in their processing that Sony does not.

 

In Brandon's video, as well as in many stills and videos from Sony alpha cameras, I can recognize these color tendencies that I've struggled with: getting skin tones natural looking in a variation of light conditions, getting nature scenes in dramatic/high contrast light to not have extra color casts.

 

 

Don't take me wrong on this one. I like the A7S and what it can do. But I'd really love it if it came with Nikon colors out of the box. My ideal camera at the moment would be some kind of mirrorless blend of D750 and A7S, although the A7S as-is comes close.

 

 

EDIT: Oh, and I forgot why I got interested in commenting in the first place - great shots Brandon! I really like the camera movements, brings such a natural organic feel to the footage. Is it mostly handheld? Monopod? Are you using stabilisation in post? I need to learn :)

I've always enjoyed your input and your reasoning on this board. If you were to purchase a new film camera today, are you saying that A7S is one of the best options? Just curious if you were waiting for something else to come to the market.  

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Rather than bog this thread down with more opinions regarding Sony's color science, since you seem to be possibly experimenting with Resolve, it may make sense for you to explore the new Color Match feature.  One of many Resolve Color Match demo videos on the Internet:

 

 

The smallest and least expensive compatible color targets are these two:

 

http://www.amazon.com/X-Rite-MSCCPP-ColorChecker-Passport/dp/B002NU5UW8

 

http://store.smpte.org/product_p/dlab-smpte-pos.htm

 

Importantly, I'm not suggesting that you have to shoot a chart for every one of your setups. 

 

However, this very useful tool will quickly get you into the ballpark and you will be able to see what it is doing to bring your images into alignment.

 

And once you settle on a particular profile, you can use this tool to create LUTs that can be used in other software platforms.

 

Additional related reading can be found here:

 

http://provideocoalition.com/aadams/story/what-good-is-a-macbeth-colorchecker-chart

 

HTH.  Good luck.

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Rather than bog this thread down with more opinions regarding Sony's color science, since you seem to be possibly experimenting with Resolve, it may make sense for you to explore the new Color Match feature.  One of many Resolve Color Match demo videos on the Internet:

 

 

The smallest and least expensive compatible color targets are these two:

 

http://www.amazon.com/X-Rite-MSCCPP-ColorChecker-Passport/dp/B002NU5UW8

 

http://store.smpte.org/product_p/dlab-smpte-pos.htm

 

Importantly, I'm not suggesting that you have to shoot a chart for every one of your setups. 

 

However, this very useful tool will quickly get you into the ballpark and you will be able to see what it is doing to bring your images into alignment.

 

And once you settle on a particular profile, you can use this tool to create LUTs that can be used in other software platforms.

 

Additional related reading can be found here:

 

http://provideocoalition.com/aadams/story/what-good-is-a-macbeth-colorchecker-chart

 

HTH.  Good luck.

 

Since I keep seeing posts claiming that the colors are just off with the A7s, in the video posted here along with other suggestions on how to get nice colors with the A7s I will reiterate this crucial bit of information. If you are shooting s-log2 with s-gamut you MUST convert from s-gamut to sRGB or Rec709 colorspace, if you do not the colors will be wrong you cannot simply grade s-gamut footage. Other than leaning towards blue, which is common for Sony, in the footage I have worked with I have seen nothing wrong with the colors coming from this camera.

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I got my A7s a few weeks ago an did some jobs with it. and what I can say is: I also don't understand that hype around it. in terms of grading (davinci ...etc.) it's one of the worst cameras I've ever worked with. especially when shooting in slog-2.
it seems to me that this mode on the a7s doesnt get that amounbt of DR it needs. the 14 stops might be correct but they are not usable. you need to light very precise to be aware of noise. all these reviews are shot in good conditions.

but a simple underexposing is gradeble better even on a 5d II or III ...
to be honset I havent't teste that camera a lot without slog ... but it seems to me that it behave better even when you are shooting avchd .. but this is something I'll check out next.

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I know I have said this before, but let me reiterate that I'd like to keep this post about how to get the best grade out of the A7s.  If you want to sell the pros of another camera as well as slag on the A7s, go ahead. But please extend me the courtesy of doing it on another thread. I'm not a fanboy as I admit and understand the A7s's flaws. The purpose of this thread is to try and solve/mitigate them as best as possible.  The upsides of this camera are undeniable and the reason I own it. The downsides are not insurmountable and worth tackling. So keep the conversation in that direction.

 

Thanks

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A very long but interesting video about proper exposing in slog2 to avoid colored noise, not just in the shadows but in the skintones as well.

 

This is excellent. Thanks for the post. Not through with it yet, but so far it's thorough and makes a lot of sense. Where people get the time to put this together is amazing.

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I got my A7s a few weeks ago an did some jobs with it. and what I can say is: I also don't understand that hype around it. 

 

That's why never look at reviews done by people who don't actually use them in the same jobs you do.

 

But seriously, the A7s is pretty good but it does have color issues. I didn't really believe it but now that I have done some grading with the a7s I feel like there are issues. Though I also believe these issues will disappear a lot when the Shogun arrives but that will increase the price of the a7s way up. It will also decrease the usability as the HDMI port is quite rubbish (as it is with all DSLR's) and will most likely break.

 

But Sony being Sony they will probably introduce the a7s II with IBIS and some more issues.

 

All this complaining aside, SLOG2 can look absolutely wonderful. Especially during high brightness situations like bright sunlight. It does give the image a "high-end" feel. Just don't use it all the time. Sometimes it's better to switch to the cinegammas, especially those that are 16-235, like Cinegamma 2. Of course then you will have to match them images but that's the thing we are learning right?

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That's why never look at reviews done by people who don't actually use them in the same jobs you do.

 

But seriously, the A7s is pretty good but it does have color issues. I didn't really believe it but now that I have done some grading with the a7s I feel like there are issues. Though I also believe these issues will disappear a lot when the Shogun arrives but that will increase the price of the a7s way up. It will also decrease the usability as the HDMI port is quite rubbish (as it is with all DSLR's) and will most likely break.

 

But Sony being Sony they will probably introduce the a7s II with IBIS and some more issues.

 

All this complaining aside, SLOG2 can look absolutely wonderful. Especially during high brightness situations like bright sunlight. It does give the image a "high-end" feel. Just don't use it all the time. Sometimes it's better to switch to the cinegammas, especially those that are 16-235, like Cinegamma 2. Of course then you will have to match them images but that's the thing we are learning right?

The first job I did with the A7s, I went through three HDMI cables over two and half weeks of shooting. Micro HDMI is shit. Then I bought the Movcam cage and have at least a hundred hours with it. I haven't broken a single connection. The port lock is that good. This would work well with a Shogun. My only wish is that Atomos  would make a smaller recorder, like a 4k Blade or something. 

 

Tried Kholi Hicks color profile and it's a huge improvement if you need a full range of tones to play with. However, sometimes, I find myself going out of S Log2 and shooting PP6 for outdoors. The 3200 ISO of SLog2 can be a POA.

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