Brylka – TooDee – PanicPost

1.3. Using OpenColorIO in Blender

OCIO vs. Filmic look and finding the way into ACES.

Blender supports more than a standard sRGB Viewer for quite a while. In version 2.79 there is a filmic tone mapping option. Unfortunately this is not ACES compatible.

I found a very good tutorial on HDRi lighting in Blender here. https://gumroad.com/l/hdr-lighting

I use a Theta-S HDR that I made in the university of Seville, Spain and set up a simple scene in Blender version 2.79.

tonemapped jpg file
Simple setup using the filmic tone mapping with medium high contrast.
Nuke 11.1 Non-Commercial in ACES 1.0.3 with sRGB(ACES) Viewer

The results are quite similar, but the goal should be to see the same image in the viewer in Blender and in Nuke. When using a Diffuse shader the differences are even better visible

Diffuse shader with RGB values of (0.8/0.14/0.10)
Although the colors look right, the contrast does not.

The obvious choice would be using the RRT viewer in Blender to match the viewer in Nuke, but by default the implementation of OCIO in Blender is misleading here. And the results too.

Colormanagement gone bad.

After finding out how to start Blender with full OCIO support, I did a another render with a different HDR from Madrid. The church is directly next to El Prado. The HDR and textures are converted to ACEScg.

With the right OCIO settings the Colormanagement in Blender looks like this.
Blender OCIO 1.0.3 sRGB Viewer
Nuke 11.1 NC ACES 1.0.3 sRGB Viewer

Now the preview in Blender matches exactly the viewer in Nuke. This is how it is supposed to be. I hope the upcoming version 2.8 will make the OCIO setup easier.