Problem with Caustics

[REDVERTEX]

Hi guys, we have a weird problem with underwater caustics.

We want to simulate caustics from a underwater lamp in a swimming pool, and we get weird "black hole" effect just above the light.


We've tried different types of light and playing with the settings but nothing seems to help.

Here is a simple scene showing the problem:
causticProblem.zip

[vlado]

When tracing the caustics, V-Ray doesn't know that the light is below the water, and assumes the caustics rays start from a medium with refractive index 1.0. So the photon rays don't bounce inside the water quite correctly.

To fix this, enclose the light in a sphere with inverted normals and the same material as the water - see attachment.

Best regards,
Vlado

[Deflaminis]

Vlado, is this similar in concept to the underwater Snell's Window thread from a while back? I feel like this came up once before.

[vlado]

Vlado, is this similar in concept to the underwater Snell's Window thread from a while back? I feel like this came up once before.

Yes, exactly.

Best regards,
Vlado

[REDVERTEX]

Thanks a lot Vlado. That fixed the problem.

[chicoone]

Wow! This has straightened out a lot of issues I had with water and caustics. I am still on 1.5 since I bought it at a better financial time and I have always only done this for personal pleasure rendering. I can't wait to get home from work to experiment with this (my day job has never been CG). Love V-Ray! Did the Under The Board Walk scene from 3dRender.com and I was very pleased with the NEW results!!!!