mental ray for Maya 2015 SP3 is now available for download here.
This service pack ships with mental ray 188.8.131.52
The most important fixes are:
- Progressive rendering in the IPR is more responsive now, especially when finalgather is off.
- Refractions and reflections are enabled for maya_volumefog.
- Deforming animation in Alembic files imported using GPU Cache is fixed for batch rendering.
- Fixes in the mental ray core:
- Unified sampling: fixed possible crash if coverage framebuffer was used in combination with unified sampling.
- Light importance sampling: reduction of noise artifacts when using point lights with non-physical falloff.
- Stabilize flushing mechanism for rendering very large scenes.
- Shader fixes:
- For layering material shaders (MILA), added support for back_scatter LPE pass.
Check out the Maya 2015 SP3 release notes inside the download for the complete list of fixes.
Complete mental ray documentation can be found here.
BTW, some of these problems were reported here and on the beta forum. Thanks for your feedback!