caustics confusion

[blinkimage]

I thought I knew this, but I seem to have confused myself:

Does the Vray environment override, whether it be a nice pale sky blue colour or a HDRI, cause caustics which will pass through glass and light the interior of my model, or are caustics only created from actual light sources in my scene, eg the Sun (direct light)?

[J_Bug]

Caustics can be produced from both GI and Direct lighting. For it to be produced by GI you would need to check the Reflective/ Refractive GI caustics boxes in your Indirect illumination (GI) rollout. To control the Direct light caustics you would use the Caustics Rollout.

Recently I was tricked into thinking these weren't working because, though I had all caustics turned off, the backside of some glass I made from a Standard material was producing secondary light onto an object, which was very close in proximity to the glass object. I think it was actually the specular highlight reflecting through to the backside that was producing the hotspot.

--Jon