View Full Version : mental ray really slow rending dont know why

07 July 2011, 07:02 AM
im doing a basic hw assignment where i have to create some basic textures and render in mental ray all i have is a area light few spheres and thats it and it seems to take a few mins each render. how do I speed it up cause i havent done that much.

07 July 2011, 08:23 AM
Well, first of all.. Are you using Final Gathering? Global Illumination? or neither of those? If neither, then ok. Anti-aliasing/Sampling of the image even if simple can take many minutes depending on how high quality the sampling is and its contrast ratio.

For sampling, set the adaptive max to either 1 or 2. No need for 3 or 4 in this case. And set the Anti-aliasing contrast to something like 0.2. Although for just a scene of a few spheres 0.1 should be fine, even 0.5 to get the best look. (Basically what this setting does is, the higher the number, the more it will try and restrict sampling to the edge of objects. But as a result, the higher you go the more inaccurate the result is and the lower the quality of edges in reflections.)

For final gathering, bring down the accuracy to something like 30, point density to like 0.1, and interpolation to around 16. Play with those values though to get the amount of quality you want. Also, don't pump the reflection and refractions too high. If you have no transparent objects, just leave refractions at 1, and keep your reflections fairly low too.

It's all about choosing choosing the level of quality you want versus render time.

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07 July 2011, 08:23 AM
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