The RT Glass shader produces a convincing light absorption effect. Is there a way to achieve this using the standard EI raytracing controls? I’ve tried mucking about with the Transmission settings and Raytrace Volume Transparency, but I don’t seem to be able to get what I want. Transmission scatters light based on volume and Volume Transparency just seems to make things more opaque, but what I’m after is the subtractive effect you see in a glass of red wine where the red becomes almost black. Ideally there’d be a simple Absorption Distance field to enter values into.

I think Material Info> Transparency>Characteristic (opaque) has the settings you are looking for.  Also the Raytrace Volume Transparency could add to this as well (by making thicker parts of the glass less transparent).

Anyone else have some ideas?

Yon