In this tutorial, I go over what I know so far about getting clean caustic renders in Redshift. I'm using Cinema 4d, but these methods should be the same, or very similar, in other programs.
I'm learning it on Katana and man I was going nuts! There is almost no material on the subject and obviously the settings are all scrambled around. Took me a day to figure this out and I thought it was a bug - now I know it's not. Cheers!
@@_UpVector_ Learning this stuff is a never ending series of little gotchas like this. Even when youve done it a hundred times, youll come back later and make the same mistakes. lol.
Really love how thorough you were with the methodology. Only thing would be maybe to linger a bit more on the settings you dial in but otherwise super duper clear! In terms of next tutorials, maybe go through settings for a realistic skin shader next? Or if too much, then perhaps lighting an interior scene (akin to a arch viz scene), it seems like you really are detail oriented (which is a great thing!). Also perhaps Render setting optimization when doing animations?
really nice tutorial. very detailed and comprehensive. understandable explanations which are easy to follow. that's how it should be for a good learning effect. please do more of them. subsurface scattering would be nice, or controlling reflections with images seems a deep topic. thanks!
Thanks a lot for the tutorial! I don't know if I'm the only one to have this problem, but doing the exact same thing doesn't help to produce any caustics. Already checked settings, tags etc. Can it depend on my GPU? Or anything else?
Double check your RS object tag visibility has caustics enabled, your light is casting caustics photons, and you're using bucket rendering not just ipr progressive mode. Should work!
@@igobyzak Thank you for your response! I checked everything, turned on the bucket rendering as well. Everything should be fine, so it seems more like a bug. Hope it will work one day haha
@@irinashamarina987 The only other thing I can think is to make sure your light is bright enough. Try cranking up the intensity of your caustics light and see if anything shows up. Also, if you haven't already, add a Caustics AOV pass and check to see if anything is showing up there. Good luck!
Just make sure your spotlights for caustics are narrow and only hitting the objects that cast caustics. Split your scene up into multiple caustics spotlights if necessary. Only the photon number in the lights affect noise level of caustics so crank those up. 10,000,000+ photons is not unheard of for clean renders. You can "blur" your caustics results with the "Search Radius" in the settings, but I've found this produces more of a muddled look rather than a "clean" look.
Hey Zak great tutorial - any idea how to turn off the spotlights "affect diffuse" & "affect specular" in RS3.06 (32mins in) so im just generating Photons - The ray tab has disappeared!
Hey thanks so much! Yeah, there are sliders now under the Details tab of the light where you can reduce diffuse, refections, transmission, etc to 0 for caustic photon emission only.
I've sped up the video during the renders, so it's quicker than it seems. But I do talk about some of the render times. I believe most of the caustics calculations happen on the processor side, not the graphics card. Make sure you're using the latest version of Redshift...there was an pretty big speed improvement made a while back that dramatically increased photon processing times.
Hey Zak, thanks a lot for this great tutorial! It seems nothing is happening for me when I emit caustic photons from the light + from the material. Could you send me the scene at the beggining so I can check if I did something wrong? Thanks!
