Author Topic: ACES Color Management Substance / Maya 2018 / Arnold  (Read 1118 times)

Hey,

I've already gone through all of the ACES threads that I could find, but I still have a question.

What I want to do:

Get .exr textures from SP to render correctly in Maya 2018, Arnold 5, ACES color management enabled. 

What is the problem?

When I export exr textures from substance and import them into let's say base color, the textures look way to saturated. (I am importing them exactly as described in the Substance Help)

I assume this is because I am using ACES color management. To check what is happening I opened my files in Nuke. Attached you can find 2 pictures.

In the first picture you can see the 2D viewer of SP on the left and nuke with default nuke color settings on the right.
The read node is set to default as well, viewer set to sRGB. All looks good.

Now I change the nuke color project settings to OCIO ACES.

On the left the SP 2D view and on the right Nuke with read node still on default (now assuming the file is ACES colorspace) and viewer on sRGB (ACES).

Color looks too saturated, same problem as I experience in Maya.

So the exr's from SP seems to use sRGB primaries? Whereas Maya maps the values to ACEScg primaries. Is that correct?

As the textures already have been made, it's not really feasible to redo everything with a Display LUT applied in SP... I am wondering if I can do a colorspace transform in Nuke to get the correct representation of the SP exr's in a ACES world.

Any chance someone of you has already done that before or has any advice?

Thanks for reading,
Caroline

hi, its too late I came across this post :D. and surely you could have solved the problem now ... but again:---
if you want to convert srgbLinear images to ACES without loosing the appearance this is what you should do in nuke:
sRGBtoACES2065-1>ACES2065-1TosRGB>ColorSpace(linear to sRGB(~2.20)>invRRT.Rec.709.Log2_48_nits_Shaper.spi3d(tetrahedral)>Log2_48_nits_Shaper_to_linear>ACES2065-1ToACEScg

you can skip first two steps as they cancel each other ...I'm putting them because if you don't want to preserve the appearance you would directly go from step 1 to step 6
and I'm using Rec.709 inverse RRT , you can use sRGB as well depending on your display or what you want.
Last Edit: November 01, 2019, 06:26:53 am