Color space input settings for Sony FS7 S-Log 2 with Matrix on in Baselight Editions

[Darren Shearer]

I have scoured the internet to see if there was any guidance in setting the input color space of S-Log 2 with Matrix on.  The usual S-Log 2 setting is way to jacked up, saturation-wise . Can anyone steer me in the right direction on this? I can normalize it manually, but thought there might be another way. 

Thank you!

Darren

[Andy Minuth]

What does 'Matrix on' do on the camera side? Does it matrix to Rec.709 primaries? 

I could create a custom space for that, but we need to know which primaries are encoded in the file.

[Darren Shearer]

Hi Andy!  Thanks so much for the quick reply.  I got the specs from my DP, but maybe you need more. 

CAMERA: SONY FS7II
SHOOTING MODE IS CUSTOM
Menu: (User/Base Setting/Shooting Mode/Custom)
RECORDING FORMAT IS HD 1920x1080 24p
    Menu: (User/Rec Format/Video Format/1920x1080 – 23.98p)
CODEC IS XAVC-I
    Menu: (User/Codec/Select/X AVC-I)
GAMMA IS SET TO: S-Log 2
    Menu: (Paint/Gamma/Setting/ON)
          (Paint/Gamma/Gamma Category/S-Log2)
DETAIL IS SET TO OFF
    Menu: (Paint/Detail/Setting/OFF)
MATRIX IS SET TO CINEMA
     Menu: (Paint/Matrix/Setting/ON)
          (Paint/Matrix/Preset Select/CINEMA)
          (Paint/Matrix/User Matrix/OFF)
 

If more data is needed, please let me know as I know I am not giving you specific REC 709 primaries data here.   I really appreciate your help with this.  We have been working Baselight into our workflow in all of our properties and this would really help.

Best,

Darren

[Andy Minuth]

Hi Darren,

I read a bit about the FS7.
For future projects my recommendation would be to leave the camera in 'Cine EI' mode and to record S-Log3 / S-Gamut3(.cine).
Only in custom mode one can choose a log tone-curve curve in combination with a custom colour matrix.
It seems like the cinema matrix is a creative tweak to 709, which desaturates the image a bit. 

I created a custom colour space for you. 
You need to put the file into
/vol/.support/etc/colourspaces/

which resolves to
Linux /usr/fl/etc/colourspaces
Mac /Library/Application Support/FilmLight/etc/colourspaces/

It would be good to know, if that is helpful in your case.

Cheers,
Andy

Sony_SLog2_Rec709.flspace

[Darren Shearer]

Hi Andy. Sorry for the tardy reply. This post eluded me somehow.

Thanks so much for this! Awesome.  Only thing is that I can't seem to get it to show up in the colourspace list on layer 1.   I did put it into the colourspace folder and restarted Avid and Baselight. Any other ideas? I am excited to give this a go with our footage.

Thanks again.

Darren

 

 

[Andy Minuth]

Hi Darren,

sorry to hear that. I just tested it here on my Mac again and it worked. I had to hold down 'Shift' to see all available colour spaces in the menu.

If you are on Windows the correct path for the .flspace file is:
C:\ProgramData\FilmLight\Colourspaces

Apart from that I would double check the correct path and ensure that there are no sub-folders in the colourspaces folder.

Thanks,
Andy

[Darren Shearer]

Hi Andy. We finally worked out how to get it loaded. The last line of meta data in the file was causing some issues, so we deleted and it loaded fine.  

As far as the transform goes, it clips and jacks up the shot a bit, so not sure if you would need more info from my side on the camera settings as I am sure you created it correctly with what you had.

Thanks again for the help on this and please let me know if you need anything else. I really like the idea of us having a proper transform instead of doing a manual "LUT" every time to get it normalized.

Our shoot department uses this setting (Matrix on) as it allows for some color in the monitoring side, but I sure would like to move us over to Cine EI mode!

Best,

 

Darren

[Andy Minuth]

Hi Darren,

interesting to hear about the issue with the metadata. Are you maybe using an older version of Baselight 5.1 or 5.2 ?

Sorry to hear that the space it not fitting perfectly. But as I said, it seems like this camera mode is more offtrack. To properly evaluate/modify the space we would need some test shots. Ideally a scene including an Macbeth ColorChecker shot at different exposures. e.g. -3, -2, -1, 0, +1, +2, +3 or whatever works.

Cheers,
Andy

[Mason Hunsicker]

I hope you don't mind if I pipe in, but as an FS7 user, I can say that the Custom mode of the camera in any sort of matrix is 709 colorspace, and seeing above, you have the Gamma in SLOG2. The transforms in camera are just custom color matrix transformations similar to an internal LUT. For some reason Sony made the Custom mode base  colorspace SGamut and SLOG2, even when you use SLOG3, the Gamut stays as SGamut, not SGamut3 or .cine.  When the matrix setting is applied, it transforms from SGamut to REC709. I noticed you stayed in SLOG2 as the Gamma, which is fine. 

Grading the footage should be treated like any 709 footage you've used in the past. There's no real LUT adjustment for using this setting, but is supposed to be a kind of in camera WDR setting, allowing you to grade however you'd like, it's a messy implementation, and definitely based on past grading methods for video and REC709 delivery for TV.

As far as using CINE EI, you can monitor on the camera any LUT you have loaded in, or use any flavor of the built in MLUTs. In the monitor section of the menu, you have SDI 1, SDI 2, HDMI, and Viewfinder. My normal setting it turning SDI 1 to off, since that will bake the LUT into the file, set SDI 2 to on, and it will affect your waveform to conform to 709 and show exposure with the any LUT adjustment you may have chosen, and set the Viewfinder to ON so the LUT can be viewed on the viewfinder. Any footage shot using this method with be whatever Gamma and Gamut you choose, and be clean, with no baked in looks, but also allow anyone on set to see the look on the viewfinder. Also, a good idea is to use any external monitor with whatever LUT you want to the camera can use the CINE EI setting without any issues. 

I've stayed away from using Custom mode for the last 7 years because the ability to work with the footage in post is problematic. Any other info you may want to learn about working with the FS7, look up Alister Chapman's page, he's got tons of info on there. 

[Andy Minuth]

Thanks for your insight, Mason.

Yeah, I assume that S-Log2 / Rec.709 should be the matching input colour space. And the cinema matrix is a creative tweak, that desaturates the image. So the starting point should be a desaturated image with proper contrast. 

[Darren Shearer]

Wow, thanks for all the insight Mason.  I apologize for my tardy reply as I've been off the grid for a few weeks. 

I will talk to my camera guy about switching to EI as soon as possible and meanwhile, Andy, I guess I will treat the footage as I would REC 709 and do my initial adjustment in Film Grade as I find that to be the best starting point.  Unless you had a wiser idea.

Once again, thanks for all the help and I will also be sure to check out Alister Chapman's page. 

Best,  Darren

 

[Andy Minuth]

On 3/2/2023 at 3:25 AM, Darren Shearer said:

I will talk to my camera guy about switching to EI as soon as possible and meanwhile, Andy, I guess I will treat the footage as I would REC 709 and do my initial adjustment in Film Grade as I find that to be the best starting point.  Unless you had a wiser idea.

Hi Darren,
yes, that is what I would recommend.

Cheers,
Andy