Material Approach for white glass light diffusers/shades?

[Morne]

Hi all

A typical white glass ball/bowl around a light globe, how would you approach that?

This sort of thing:
https://cdn.shopify.com/s/files/1/11...g?v=1455716540
But also cylindrical for sconces etc

Setting refraction high like 240,240,240
and refract glossy low like 0.6 or 0.7
...this produces nice BRIGHT spaces as the light seem to travel further and in general a cleaner faster render. The light may BURN heavily right where the fitting is against the wall or ceiling. My VRayLights have Radiant Power of about 1.5 which is same is 60W light bulb.

In contrast, LOW refraction like 70
HIGH refract glossy like 0.95
...makes the glass diffuser look much more natural and you don't get that heavy burn against the wall or ceiling. BUT this gives MUCH darker renders that also render MUCH LONGER

Thoughts?

[FLP]

Perhaps a different approach?

[Morne]

OK so instead of refraction, you'r going for 2sided. WHich is quicker and produce less noise.
The glass looks nice, BUT does that vraylight inside there give off enough light to go for a 60w light globe and still light the space...
Could you run a quick test with all the lights switched off except the inner one, set its "radient power" to 1.5 and expose your cam with ev 8

[Morbid Angel]

you won't be able to get the result you are after by using physically accurate approach as you found out already, it takes too long. More then that, any light that pass through glass, comes out as caustics on the other side, so "Affect Shadow" is really already making it a physically inaccurate result, that's why you are not getting proper result. I also doubt that if you use caustics you will get proper result either, with glossy glass it just wont happen. What FLP suggested is best bang for the buck, just fake the brightness by other means.