Thanks for chimimg in Matt. I used 0.5 and AA6, but subdiv at default. I realized that the grain comes from the max paths settings, which I kept at 'exterior' (outdoor camping
).
Here's another test on a geode I made earlier, with higher max path settings (49, I believe). I really like this effect.
@KyL ; did you have the skin textures before or after the glass shader? I had them after the glass, but it seems like its effect is diffused quite a bit by the previous glass shader. Still need to get the hang of this, obviously.