Issues Raytracing Diamonds in Rhino 7: Why are diamonds rendering grey?


I’m having a problem raytracing diamonds in Rhino 7. What should be colorless diamonds are rendering as if they were dark salt and pepper diamonds! The weird thing is that the reflectivity and dispersion is there, they are just colored dark grey instead of being colorless.

When I try raytracing the same model in Rhino 6, it renders normally and the diamonds are the correct color.

Have there been any changes made to Rhino 7’s properties or environments that I should be aware of? Thank you!


The second render result looks like a different encironment (and dufferent orientation) was used. But it is hard to say without a file.

Hi Nathan,

Thankyou for your answer. It doesn’t seem like the issue is related to object orientation. I tried raytracing a file with the object in the exact same orientation in Rhino 6 then in Rhino 7 and the issue persisted.

Seems like Rhino 7 has more pronounced black undertones in its renderer that are affecting the way the diamonds are rendering?..
I wonder if there’s a way to control that.


Could you share a ring model with me via ? I’ll gladly take a look to see what the difference is and where it comes from. It could be change in Cycles that I didn’t catch when upgrading Cycles between Rhino 6 and Rhino 7.