Hi Hans,
Carried out a few more tests, the newer caustics settings only seem to make a very slight difference. They have improved the 3 coloured vases on the table, one of my previous test scenes, allowing light placed slightly further away to still pass through. Haven't made much difference to your blue bathroom scene though.
To make sure they were working I closed the wall at the end (preventing caustics photons escaping) increased the height of the yellow wall, moved your working colourd glass blocks to the middle, used only one very large 150cm light half way between the floor and ceiling (at the end of the bath) to the light wouldn't blow out and could see a point at which the caustics rays may stop.
Finally I turned off the ceiling light so could carry out caustics comparison renders.
"Compute glass transparency:" Off (Sunlight off)
"Compute glass transparency:" On (Sunlight off)
Other settings can be used for caustics but they make for very slow and sometimes patchy renders, where the light pools unnaturally.
With caustics, there isn't really one set of settings, that suits all, so trying to find the best settings before, was always going to be a bit of a compromise. Something that works for most circumstances and works quickly is probably most appreciated.
Have you done anymore with the scene, or was it built just to test caustics?
Take care,
db4tech
