[Max] Caustics rendering in IR but not in final render

[NotRealGabriel]

Hi there! Im having some trouble showcasing caustics on the ceiling above this pool. First pic (20.jpg) is the final render and second pic (Caust1.jpg) shows the IR. How can I make the final render have caustics? Caustics setting in performance is on. I also tried having a source of light below the water pointing to the ceiling but it doesnt generate strong caustics like I want to.

[maru]

Hello, this is an interesting case, because usually people wanted to get rid of caustics in such areas. :)

I have 2 suggestions:

1) Try a daily build if you are willing to - just please remember that it's an experimental version and you should keep backups of your scenes - https://forum.corona-renderer.com/index.php?topic=38385.0
The reason is that there are already some caustics improvements in the dailies.

2) Adjust caustics solver settings:
Enable development/experimental stuff rollout - https://support.chaos.com/hc/en-us/articles/4528523195537
Go to Performance > Caustics solver settings
Increase Photon count from the default 5 000 to a higher value (you can try with 15 000 and then try again with higher values like 20k, 25k, etc but at some point you will most likely run out of RAM).
Optionally: increase lookup radius from 1px to a higher value like 1.5 or 2px (this should help especially when rendering in resolutions higher than 1080p).
Optionally: in the Performance tab, lower GI vs AA value from 16 to 8 - this way caustics will be calculated more often and will get better quality, however this is at the cost of other effects such as the overall GI quality in your image

[Beanzvision]

Hi there, coming from C4D, maybe faking it with a Rayswitch material could help as well? A regular water shader for the visual and something highly reflective to ''enhance'' the caustics. Some food for thought :)