Mental Ray Rendering Engine Maya Help


Official Mental Ray Forum at NVIDIA

 Autodesk Maya Mental ray Help Pages

Easier Mental Ray Rendering for Design Workflows (pdf)

Global Illumination Render Basics Tutorial by Stuart Christensen Maya TUTORIAL

21 “must see” Mental Ray tutorials

Tutorial: Multipass rendering in Maya and Mental Ray

Clay Rendering Tutorial for Mental Ray

Mentalray is missing. Help, I can’t find mentalray.  Mentalray is not there.
You do have mentalray regardless of whether you’re using student/education version or the full licensed program.
FIX:  Window – Settings / Preferences – Plug-in Manager and then scroll to the very bottom and check both boxes next to mayatomr.mll

Mentalray won’t render
Possible fix:  Make sure you only have one version of Maya open.
Sometimes it won’t render if you have two versions of Maya (under the same license) open at one time.

Mentalray won’t render things from the Visor.
Possible Solution:  The things you create in the visor in paint effects must be converted to polygons before you are able to render.  Modify – Convert – Paint Effects to Polygons

Mentalray won’t render hair or fur
Possible Answer:  Convert to polygons

Warning: (Mayatomr.Scene) : output data type “rgba_h” not directly supported by image format iff, conversion performed by mental ray
Possible Fix:  Go into your Render Settings and change the image format so it say TIFF.
Looking for more solutions:  Check back


CONFLICT WARNING:  Rendering will not stop
API 0.0 166 MB warn 302018: type conflict: “input” is type vector, “maya_file” returns type color
API 0.0 166 MB warn 302018: type conflict: “specularColor” is type color, “maya_multdiv” returns type vector

When does this happen?
A.  Using Paint Effects from the Visor
B.  Physical Sun an Sky
C.  Looking for more situations …
Looking for solution:  Check back


Mental Ray out of memory

Possible Fix:  Batch render, go to the options and set a manual memory amount.  If you have 16 GB of RAM, set the manual memory to 8.  If you have 8 GB of RAM, set the manual memory to 4.  If you have 4 GB of RAM, set the manual memory to 2.  If you are running a 32 bit Maya, then 1.5 gigabytes is the maximum a 32 bit system can spare for one process.

Possible Fix:  use pixero shaders – he has 2 shaders to solve this problem vector -> rgb
and rgb -> vector.  his site is – from forum

I don’t think this is a mental ray issue, but it is here for now until I figure out where it should go.
Error: line 0:  This scene does not have any renderable cameras.  The renderable status can be set in the camera attribute editor.
Possible fix:  Outliner and click on the camera.  Look in the attribute editor under Output Settings and make sure the renderable has a check in it.