New mental ray features with 3ds Max 2009 and 3ds Max Design 2009:
A new library of easy-to-use, physically based materials for mental ray based on manufacturing-supplied data and professional images. These materials give you fast access to commonly used real-world materials such as professional wall paint (glossy or matte finish), solid glass and concrete.
New mental ray Proxy Objects
A new primitive has been added that lets artists cache high-resolution meshes that be demand-loaded at render time. This saves memory, increases performance and allows the artist to render larger scenes.
Enhanced Production Shaders
A new lens shader enables mental ray to evaluate only those rays that intersect specified objects, a new matte/shadow material can capture indirect illumunination, and a new chrome ball shader can quickly create reflection maps.
Enhanced Per-object Render Settings
Additional object-level settings are available that allow more control over renders.
Improved Final Gather and GI
New final gather and GI only settings allow artists to quickly cache these types of maps for improved animation rendering.
New BSP2 Raytrace Acceleration
New, faster binary space partitioning acceleration improves large scene rendering performance.
New mental ray Render Elements
A new render element for extracting HDR data from Arch & Design materials and another new render element allows the user to define the type of data they would like to extract from the shader tree.