FS7: S-Gamut in Custom Mode on Sony FS7

Joshua Milligan

Joshua Milligan

Well-known member
Hey fellas. I was wondering if when you shoot in Custom mode with S-Log2 or S-Log3 and have the Matrix turned off, does the camera default to S-Gamut? I've read conflicting posts where some say that it is S-Gamut and some say that it isn't. I don't shoot in Custom mode very often, but every now and then I have to. I wanted to know what the camera was working with when selecting S-Log in Custom.

Thanks and Happy Easter!
 
Josh, I'm pretty sure that all Custom uses in S-Gamut in the FS7 .
It is strange that the A7iii or A7Sii give you a choice of a bunch of different Gamuts and you don't have that in the FS7 but that's the way it is. Sony departments often don't talk to each other.
 
Thanks for your responses! I figured it was just S-Gamut, but I wasn't sure if it was a rec 709 style like Tom said or not. I wish it was just S-Gamut so you could at the very least use it in conjunction with the CINE EI Slog2 when necessary. I couldn't find any info on this online.

So if it is rec 709, how does that work? It seems odd that you can select Slog2 or Slog3 in custom mode without the Matrix turned on, but have no idea what color space you're really in.
 
S Gamut is just a color space not a gamma so it is gamma independent. Slog2, Slog3, 709, hypergamma, Std gamma - doesn't matter. The Matrix is within that color space. You are right that Slog2 is designed for S Gamma so its a good match even in Custom if you can make that work for you even though you can't use a LUT.
On the other hand there are some people ( not me) who use SLog3 in Custom also using S Gamut. It won't be the end of the world. In the A7 you can match any gamma with any gamut .
 
I don't have the camera in front of me but as I recall its pretty straightforward. They are choices in the gamma menu along with Hyper gammas and Standard gammas. etc. However there are no LUTS fro them, so you will have a very flat desaturated image. Someone on this forum liked to shoot with Custom SLog2 and crank up the saturation but its certainly not a standard way to use Log. Generally just not done. You might find his settings if you do search here. A few other people have used Slog3 in Custom so they can white balance or use more gain and they've been happy with the results in post. You are free to experiment but there's no roadmap.
 
Joshua Milligan said:
How do you go about setting up Slog2 or Slog3 with S Gamut in Custom mode? I guess that’s what I don’t understand.
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Yes I've used Custom SLOG2. To do so I found I have had to develop my own Matrix to suit. The pluses are you can now white balance and you have the wider dynamic range of SLOG2. It handles the highlights better but you still have to be mindful of protecting them while you shoot. The other side of the coin is that you are running at the base ISO of 2000. But should you need higher gain than 2000 then it is available. This is the matrix I ended up with. Generally pretty well accepted by clients. No objections so far. This was originally developed to mix FS7s with Panasonic LTs shooting in V-LOG 709 mode.

Chris Young

https://www.youtube.com/watch?v=iQRs-8CbohQ&feature=youtu.be
 
Only EI Mode has Sgamut/Sgamut3/Sgamut3Cine. In Custom Mode there are subset styles of 709 available to F55 only. They use naming convention of "like."

- Sgamut3.like
- Sgamut3cine.like
 
Tom Roper said:
Only EI Mode has Sgamut/Sgamut3/Sgamut3Cine. In Custom Mode there are subset styles of 709 available to F55 only. They use naming convention of "like."

- Sgamut3.like
- Sgamut3cine.like
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Yeah that's kinda what I thought. I was under the impression that Custom mode, even when in log, doesn't record in a true S-Gamut, but rather in a Rec 709 file that may stem from S-Gamut, but is already baked into a Rec 709 file type. I wasn't sure though if that was the case when Matrix was turned off rather than selecting one of the Rec 709 options, but it looks like even when off it's still in a Rec 709 space.
 
I'm somewhat confused about Gamut and Gamma because while S-Gamut is only a Gamut, 709 seems to be both a Gamma and a Gamut. I think of anything in Custom except Log as being different flavors of 709 ( hypergamma, standard 5 etc) because they're designed to be seen directly on a TV - but is that correct? This is even more confusing to me in the A7iii where you can have choice of a number of "color modes" some of which are labelled as gamuts but they also include 709 and things like Pro or Still that that sound more like "looks" or different matrixes. Is Pro or F55-Like or Standard another gamut or a subdivision of sGamut and 709 or what?
 
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LennyLevy said:
I'm somewhat confused about Gamut and Gamma because while S-Gamut is only a Gamut, 709 seems to be both a Gamma and a Gamut. This is more confusing to me in the A7iii where inside of 709 gamma you can have choice of a number of gamuts some of which sound more like "looks " to me than actual gamuts, but then a agin I don't really know the difference. Is Pro or F55-Like or Standard another gamut like S-Gamut or are they looks?
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That’s partly what is making me confused too. This is one thing I don’t like about Sony’s F series cameras. There’s too many color options that don’t exactly make a lot of sense. Simplicity is bliss.
 
LennyLevy said:
I'm somewhat confused about Gamut and Gamma because while S-Gamut is only a Gamut, 709 seems to be both a Gamma and a Gamut. I think of anything in Custom except Log as being different flavors of 709 ( hypergamma, standard 5 etc) because they're designed to be seen directly on a TV - but is that correct? This is even more confusing to me in the A7iii where you can have choice of a number of "color modes" some of which are labelled as gamuts but they also include 709 and things like Pro or Still that that sound more like "looks" or different matrixes. Is Pro or F55-Like or Standard another gamut or a subdivision of sGamut and 709 or what?
Click to expand...

You are correct. 709 is both a gamma and a gamut, generally 2.4 or 2.2 log power gamma and 709 color space primaries. STD5 and hypergamma are variations; something slightly other than conventional 2.4/2.2 gamma but each still a color subset within the 709 addressable primaries. For televisions, 2.4/2.2 gamma and 709 gamut are fairly consistently applied, but for cameras more loosely applied as various styles and naming conventions, Vivid, Natural, Sgamut3cine.like; but still are subsets contained within 709 boundaries. This is understandable as cameras are creative tools, televisions are not. Only EI mode gives you access to the Sgamut/Sgamut3/Sgamut3.cine color gamuts but even that does not necessarily mean every sensor can actually capture the full addressable color range.
 
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