User Guide > Rendering and Render Setup > Lighting > mental ray for Maya Lighting > Troubleshoot mental ray for Maya shadows >
Troubleshoot shadows are not motion blurred when
the rasterizer is used
When you use the rasterizer with motion blur, the resulting shadows may not have motion blur. To obtain motion blur, increase the Time Samples to greater than one in the Motion Blur section in the Render Settings: mental ray tabs, Quality tab.