Caustics subdivs limit?

[TheLooopCGI]

Is there a limit on caustics subdivs for lights?

I have about 5 lights in the scene with caustics turned on and 5000 subdivs each. All renders great. Then I want to make a final render and turn up caustics subdivs for each light to 100 000 but it renders quite strange and different. I tried to lower to 90 000 and then the whole refraction in the water is black...

Any idea please?

[vlado]

About 60000 (about 2^16) is the most you can get, otherwise the number of photons does not fit into a 32-bit integer value (about 4 billion photon rays - the subdivs number is squared to get the total number of photon rays).

Best regards,
Vlado

[TheLooopCGI]

Oh, I see. Thanks for explaining. It would be great to see it handled by float numbers in 2.0. Computers are getting better and it's more and more affordable to use higher subdivs these days... But I'm sure you're aware of that. Thanks again for answer.

[TheLooopCGI]

Hmm, is it 60000 for all the lights combined or for each light? I'm down to 30000 per light and it's still not working.

Before you responded I actually tested 70 000 for each light and it worked... at least it seemed to look okay, but maybe the result was not correct?