Nuke Display - sRGB (ACES)

Hi everybody,
I’ve a question concerning the sRGB(ACES) Display in Nuke.
On this topic from The Foundry website (https://community.foundry.com/discuss/topic/135319/can-t-reproduce-the-same-look-with-linear-srgb-renders-in-nuke-ocio-aces-config#1186591), it seems that there is a shaping curve different between sRGB(ACES) and sRGB standard.
Does somebody know the function to recreate these curves ? Or where I can find them ?

Thank you very much and have a good day !

Stephane

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If you really want to dig into the maths of the tone-mapping curve you need to look at the CTL in the aces-dev GitHub repository. It is a concatenation of the segmented_spline_c5_fwd in the RRT, and the segmented_spline_c9_fwd in the sRGB ODT, followed by the standard sRGB inverse EOTF.

But is that really what you are after?

You can sample the curve as a 1D LUT from Nuke’s OCIOColorSpace node with input set to “Utility - sRGB Texture” and output set to “Output - sRGB”. But the total effect of the ACES pipeline is more complex than just a 1D LUT.

I finally found my solution. Affinity users have the same problem of not being able to properly go from ACES to a publishable format. It put it into a simple script around the ocio and oiio packages on homebrew. The script is currently for single files, if you need sequences, just loop over a folder of files.