Hi,
I have problem with making colored glass in YafRay, my light source not going through glass. I don’t know problem, is it a material (glass) not good enough or it’s a lighting problem?
If it’s lighting maybe someone could help me with a scene.
I believe to achieve caustics, you need a Photon Lamp. I can’t tell you how to tweak the settings because I can’t do that with any success either. =P
Photon lamp yep. Just dupe your spot and turn the new one into a photon. Lotsa tweaking to be had, but the main hoop to jump through is to have your depth in your photon spot turned up for every face the photons have to go through, min 2-4 for a regular cube. Also must be on Method Full and quality at least low.
Thank you very much 
yes it was YafRay Shadows and photons depth and blur.
I have an example made in older blender version. Where this kind of effect made with area lighting. It was blender 2,37 I think
