IOR setting missing from materials

Rendering
1

Hello and thanks for helping.

Just upgraded from Rhino 7 to 8 on my Macbook Pro M1. Having major bug and crashing issues but focused on the issue when importing a Rhino 7 model with an Custom physically based iridescent material into Rhino 8. The material in Rhino 8 is missing the crucial IOR option that is present in Rhino 7. I also don’t have the option to add an opacity layer. When I try to recreate from scratch, I don’t have the option to build the material with colors assigned to the Base, Gloss finish, reflectivity, and transparency.

Basically, the iridescent material looks terrific in Rhino 7. In Rhino 8, it just looks like a reflective pink color and assuming it’s due to the lack of IOR customization.

See pics for reference.
Kind of stuck here and would appreciate some help please.
Thank you in advance.

Bottle Rhino 7
Bottle Rhino 8

2

The IOR setting appears only after you change opaque to be less than 1.0.

3

Ah, I see. Strange that in Rhino 7, transparency is set to zero and can still manipulate the IOR. Anywho, I adjusted but the effect was drastically different. Tinkered with the settings a bit and was able to get it close to the original. Many thanks!

4

I think it was part of making the UI simpler. Typically IOR is useful only when opacity is non-zero. I guess this is a corner case that wasn’t thought off.