Disable gamma baking with Separate render channels

[flat]

Is there a way to not apply gamma to elements such as VRayNormal and VRayVelocity when saving Separate render channels (out OpenEXR 16/32bit)?

Using with V-Ray 5 for 3ds Max

[hermit.crab]

I am not entirely sure, since the 3ds Max module is used in that scenario. I'll write back with more information.

[hermit.crab]

The output difference between multi-channel .exrs and separate render channels .exrs is how the data is written, rather than a gamma application. With multi-channel .exrs, the normals (or velocity and other such elements) are written as vectors, where the X,Y and Z coordinates are numbers ranging from -1 to 1. With separate render channels, however, such vectors are written in RGB colors (0-255 for 8bit images, which corresponds to 0 to 1 in .exrs) since it goes through the 3ds Max module. It is possible to convert the colors to vectors through an Expression node in Nuke (see conversion formula here).

[flat]

Thank you for the detailed information.
It was very helpful.

By the way, is RGB forced for single channel OpneEXR?

Separate render channels are output in RGB even with vrimg2exr.exe that does not go through 3ds Max I/O.

If possible, I hope that vrimg2exr.exe will have the ability to output vector elements in a single-channel OpenEXR vector.

[hermit.crab]

That wouldn't really solve anything since the effect concerns all "Separate render channels" image formats, including .vrimg (since RGB colors are expected as an output with this option), which you most likely use as an input in the vrimg2exr.exe.

[flat]

OK. I understand the specifications.