You can render passes in Maya that split up a beauty image into layers like reflection, diffuse, specular etc.
One option is to save these passes in float openexr files(for ultimate color fidelity).
The beauty exr file reads just fine in photoshop.
The render passes however show up as black in photoshop even though they are not as verified by imf_disp,
a viewer program that comes with Maya.
I know the problem is that the header in the renderpass openexr file is the name of the "renderpass"(eg "specular") as opposed
The solution for me has been to use a program that comes with Maya called imf_copy to replace the headers of the renderpass files.
in windows I use the following command line:
"C:\Program Files\Autodesk\Maya2012\bin\imf_copy.exe" specular.1.exr specular_forphotoshop.1.exr
This results in the new file specular_forphotoshop.1.exr which is no longer black when opened with photoshop.
I have used ProEXR and yes it reads extra channels.
Renaming the layers to nice labels and then setting the appropriate composite modes as they are loaded.
If you have ProEXR installed, it should become the default plug-in for opening EXR files. So you open the file and have layers, with which you may do whatever you wish.
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