linear sRGB footage in Nuke ACES darker

Hi there, I’ve seen some people having similar issue but still didn’t find a solution…
I have cg background from redshift render in AcesCG that I need to compose with linear sRGB footage (GH5 natural profile exported as image seq exr through FCP). The footage looks great with the normal Nuke Color management. If I switch to ACES 1.1 and use utility-Linear-sRGB for my footage, its close but my dark are crushed.
My understanding that there’s a extra S curve in the ouput viewer that could cause this… but Its there any way to make it looks the same?
If not, how could I convert my cg ACEScg footage to look right in normal Nuke color; which node and which Lut? I’ve been trying many but can’t find the right one yet…

Thank you so much

The default Nuke is un-tone-mapped and has no s-curve. Aces has an s-curve (good) that tends to crush the shadows (not so good).

If you are doing the final color grade in Nuke you could just do a lift or offset to bring up the black levels to your liking. Likewise if you are passing on EXR files to DI they can do the same there. The information is not lost.

If you really want to have the Nuke default look you can use the un-tone-mapped display transform from the sample OCIOv2 config, but I would not recommend this. As a wise man once said “Friends don’t let friends display 2.2 gamma without an S-shaped curve“

Hi Derek, Thanks for the reply! so sorry for the delay!
I played with the lift and curve and just coudn’t get it the way it was…
OCIOv2 probably could help me figure out a solution but I still didn’t figure out how to install it on my 12.5 Nuke…I guess I need Nuke 13 at least. Anyhow, I end up for that project staying in normal Nuke as Redshift was giving me a pass with baked in ACES transform and I used the unclamp ACES AOV to drive my glows and glints.
Thanks again!

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