Frosted glass

[Peter Milner]

The frosted glass material here is created solely by adding a fine sand texture.

The glass partition is modelled as solid.

The background image shows through the frosting clearly without being broken up and also shows through in areas where it shouldn't be visible.

I shall see what happens if I use blurry transparency instead.

[Roy Hirshkowitz]

Have you tried the new build yet?

The Pathtracer doesn't know anything about interiors or exteriors-- that setting is pretty meaningless. The penalty for convergence of glossy materials is more likely to occur on those drawings where the sky is blocked-- smaller windows, windows at a distance, etc..

[Peter Milner]

After a quick test it appears that both problems seem to have been sorted.
Thanks Roy.

[Marc Chaumier]

So, for you Peter, what is the best solution for frosted glass (alone or mixed with clear glass)? Modeled as solid; simple faces textured, pasted on glass solid; simple faces, one beside the other ? Blurry transparency or procedural sand texture?
Thanks.

[Peter Milner]

For frosted glass I would suggest the following as a good starting point:

Reflection - Intensity 0.8, Sharpness 0.2, Fresnel 1.0
Transparency - Intensity 1.0, IOR 1.5, Blurriness 0.8

If you're applying a thin region of frosting to a glass object, make sure you set the IOR of the frosted material to 1.0 and space the region 0.5mm in front of the glass.