Update 09/09/2014 = Tutorial => http://www.3d-station.fr/2013/05/28/dispersiondiffraction-de-la-lumiere-avec-3dsmax-et-mentalray/
I recently doing some test rendering volumetric caustics with MentalRay, and after that, I wanted to see if it was possible to recreate a prism of light.
Unfortunately, there is no option of dispersion in the Arch & Design Materials.
Master Zap explains a method with a script. But it multiplies by 3 the rendering time.
There is a plugin / mentalray shader that allows for that. Prism Photon 1.0.0 by Ralf Habel
It is here:
After some test you can see the result.
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