Here's my Diamond Shader ver. 01
It has some nice features :
1. No mental ray needed
2. Fast enough with raytracing (software render)
3. No HDRI, GI, AO & Photonics stuff
I use ramp for the chromatic abrev.
To use with MR, adjust the BM_Diamond_Chromatic_ramp1 color.
Just render it to see the chroma beauty of it :)
Note : sample included
Any suggestion and question to compoziting@yahoo.com
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