I am using Mental Ray and its mr photographic exposure control. However, when I try to render the same file but on a different computer (with the settings exactly the same) there is a visable difference in lighting.
I have also tested:
No exposure control at all: both files rendered correctly.
Using logarithmic exposure control: both files rendered correctly.
It only seems to alter when I use mr photographic.
Let me ask, are you viewing the rendered results on the same computer meaning do you collect the renders from all the machines and then view them side-by-side on one machine? If not, you should only evaluate them that way as each monitor, even if calibrated, will display differently. That doesn't affect the file, just the display.
If you are in fact viewing them all together on the same monitor try checking your Gamma setting on all machines to make sure they are all set the same way. I had issues with the Gamma settings being different, some default and some custom, which led to rendered frame variations.
If that doesn't help maybe someone else will have a suggestion. Good luck.
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