Purpose:
To find and calculate the difference between diffuse and glass color inputs for allowing end users to use texture maps as intended without having to do the math themselves
Hypothesis:
Both the linear and color space curve will need to be changed as to allow results as expected
Materials:
– Maya 2018.2+
– RenderMan for Maya 22.1+
– Time
– Adobe Photoshop CC 2018 or photo editing software capable of opening 32-bit image files
Set-Up:
Two shot glass like objects will sit in identical lighting conditions but mirrored
One will have a multiplyDivide node plugged into its diffuse color input while the other will have the same multiplyDivide node plugged into its glass color input. A cube will have a PxrConstant with its emission input also connected to the multiplyDivide node
Rendering will be done at 540p with PxrVCM unchanged other than ray-depth increased to 16 diffuse and 8 specular
Conclusion:
Only the color space curve needs to be altered for best effect
Data can be found attached below including the scenes (Maya ASCII) and renders (OpenEXR-Half Float) included.