3. Render settings — mental ray

Caustic effects only render in mental ray, so it’s good to set those up early. Keep in mind that this is a finicky combination of settings that are hard to troubleshoot and test. Forgetting one small setting can make parts of the effect disappear, so these notes are as detailed as possible to hopefully make this process a little less insane.

1. Open “Render Settings” using fourth render icon in the
   “Status Line” (right)

2. In “Render Settings” window:

   1. Select “mental ray” as the renderer

   2. “Indirect Lighting” tab > “Caustics” rollout > enable “Caustics”

   3. “Quality” tab > “Raytracing” rollout > set both “Reflections” and ‘Refractions” to “5”, and both “Max Trace Depth” and “Shadows” should be greater than or equal to 4

   4. “Features” tab > “Extra Features” rollout > enable both “Auto Volume” and “Photon Auto Volume” and set “Volume Samples = 3”

Test render 2

If you do a test render at this point, you will notice that mental ray takes considerably longer than they Maya Software Render because it is calculating more raytrace effects. For example, the environment below the water surface will appear shaded by shadows cast by the water surface now because the mental ray renderer has raytrace shadows on by default.