Correct usage of RCM and RikshaDriver's ProTune Transforms?

Hi all,

please help me out with RCM and our RikshaDriver's ProTune Transforms (https://github.com/xtremestuff/protune-transforms). I can get things spot on with ACES, but I struggle to find any RCM configuration to match that using GoPro_Protune_Rec709_DWG_DaVinci-Intermediate.dctl.

I need to mix with other Rec709 footage and output is plain Rec709. Reason I don't what to use GoPro_Protune_Rec709_Rec709_Gamma-2.4.dctl is that I get all kinds of strange artifacts when using it with RCM. It works fine when manually placing the transform on the last node on the color page, though.

So actual question is, what is a correct RCM configuration to use for GoPro_Protune_Rec709_DWG_DaVinci-Intermediate.dctl with plain SDR Rec709 output?

I tried the settings attached, but results are completely off and in no way or form match ACES. Input is bypass and clips have the transform assigned via LUT menu.

Thanks and best regards.

Hi Peter,

You're likely having issues thanks to the problematic DaVinci Input DRT.

You should set the Input DRT to None.

Your input Color Space at the individual clip level also needs to be set to "Bypass" (for Resolve v17.4.4 or earlier) or "Same as Timeline" (since Resolve v17.4.5).

I think you're observing artefacts with GoPro_Protune_Rec709_Rec709_Gamma-2.4.dctl in RCM because the footage likely contains negative values which DaVinci Output DRT doesn't like.

Setting Output DRT to "None" should make the artefacts disappear.

Thanks, removing input and output DRT fixes it. Now what do I need to change to get LGG wheels behave similar to regular Rec709 mode? I'm confused to what they do in color managed. Gamma and Gain behave like the same thing. I found a similar thread, but no real solution?

viewtopic.php?f=21&t=120428

A couple notes on your transforms: GoPro_Protune_Native_Rec709_Gamma-2.4.dctl always produces artifacts like black boxes with RCM. No matter if DRTs disabled.

I also had an issue with the same transform producing green/purple fringes in dark shadows.

Surprisingly this is better with ACES. But then I tried your Native Rec2020 transforms with RCM and it is even way less. I always attributed this fringing to the 8 bit codec, but that doesn't seem to be the issue.

Leeming's Native LUTs are completely unusable in this regard. Compared to those all your transforms are from another world.

For now I use these settings with your 2020 transform. No artifacts, color wheels behave as expected, very little fringing.

Is it technically correct what I am doing?

I've updated the Gamma 2.x transforms to clamp the negative values. That should correct the artefacts.

You should use the transform with the appropriate color space / gamma based on the target timeline. SDR Rec.2020 uses a Gamma 2.4 curve with a Rec.2020 color space.

Do you have any raw samples where you're observing purple fringing? I suspect what you're seeing may be noise?

Thank you so much for your work! All artifacts are gone.

Still one question: When working in Rec2020 SDR 2.4 Gamma 100 Nit preset and using your 2020 transform... why are all values sitting at the bottom of the parade? Shouldn't they be equally exposed in a Rec2020 100 Nit and Rec709 timeline?

Thanks again.

There are no Rec.2020 Gamma 2.4 transforms. The only Rec.2020 Protune transforms are the DaVinci Intermediate gamma ones.

If you use a DaVinci Intermediate preset on a Gamma 2.x timeline, then Resolve will pull a Gandalf... "Go back to the shadow!", which is what you're observing.

Please help with using ACES or RCM and RikshaDriver's ProTune Transforms.
I have gopro footages Protune Native WB and need to correct cst in DR 18.1
I've followed instructiuons from https://github.com/xtremestuff/protune-transforms

ACES recives something overexposed with GoPro_Protune_Native_ACES_v2.dctl (screenshot attached)

You have no output transform set in the ACES settings.

The default Linear / AP0 would be assumed as the output in that case... which is likely not what you want.