Из mental ray for Maya architectural guide:
Second, the mental ray over-sampling is guided by the pixels in the main frame buffer. If these are left in full dynamic range, mental ray may needlessly shoot thousands of extra samples in areas of "high contrast" that will all be tone mapped down to white in the final stage.
Second, the mental ray over-sampling is guided by the pixels in the main frame buffer. If these are left in full dynamic range, mental ray may needlessly shoot thousands of extra samples in areas of "high contrast" that will all be tone mapped down to white in the final stage.