ACES color difference Texture vs. Color Picker

[doppelgaengerdigital]

I have ACES workflow setup. Environment variable is set.
Rendering Space ACES - ACEScg
View Transform - sRGB (ACES)

Texture Color Space is Utility-SRGB-Texture
In the Maya Color Picker the Mixing Color Space is locked to "Output (sRGB)" (should this be another one?) and Color Management is activated.


I have 2 simple Shaders with self illumination. One gets the Texture, the other the RGB values. But they look different in Viewport and when rendered.

Am I missing something here or is it a Bug?

[hermit.crab]

I think the Mixing Color Space shows the rgb values after the transform, so setting them as the same values as in PS would yield different results. Try disabling it then enter the specific shade of blue and re-enable it.

P.S. This is a good read: https://docs.chaosgroup.com/display/...Workflow+Setup

[moshev]

Hello,

The view transform offered by the ACES OCIO config file includes an additional filmic tonemap curve (i.e. the ACES Reference Rendering Transform), which is why your values do not match - Maya's colour picker operates in view-transform space with the RRT applied, while your texture is in regular sRGB colour space. See explanation at https://community.acescentral.com/t/...b-rrt-odt/1779 , and the diagram here: https://knowledge.autodesk.com/suppo...D3F29-htm.html

To work around this, you can unset the OCIO env variable and simply use the built-in ACES support in Maya and V-Ray, which does not perform any additional tonemapping when applying the view transform (i.e. it applies only the Output Device Transform, without the Reference Rendering Transform), or use a custom OCIO config file with an sRGB output that does not include the RRT.

[doppelgaengerdigital]

short follow up: The color management was working just fine the way I set it.
the problem seemed to be with mash's color node. I had 2 nodes laying on top of each other. One for randomizing with a ramp and the other for coloring back to constant blue. The ordering of those layers seem to influence how colors are displayed and rendered. (weird behaviour. I guess it's a Mash thing?)
Although I don't really know why. There is no blendmode set. Everything should blend 100%.
Also color difference only affected the blue color, which was weird also...

BTW: I rolled back to Vray Next, because I had crashes every 3 minutes on this project. No crashes since...