Character animation, GI & SSS? Anyone got any advice on this test?

[ajlbeer]

Hi there folks. I'm very new to V-Ray (and lighting for that matter), though I have been trying a lot of the tips on reducing flicker here...to limited effect. I figure I am overlooking something experienced eyes may help me resolve?

Please don't mind the roughly blocked animation. The biggest fix I've come across seems to be turning off "store direct light", which resolves a lot but increases the render time by a factor of 3 :v(

Has anyone got any experience with character animation, GI & SSS?

Have a look at this test...


This is using brute force for both primary and secondary bounce and the render time for a 1080p image on a farm with 12 CPU's is about 12 minutes a frame. I can reduce the render time to 4 minutes and less using irradiance map primary and lightcache secondary bounce, but the eyes begin to flicker more intensely (despite using high animation settings). My next step was going to be drop the GI and fake it with lights, it just seems like I might be throwing the baby out with the bath water there.

Any good leads on character animation settings using Vray? In particular with SSS? I saw Richard Roseman's beautiful work and his post from 2004 but the links he posted have died.

Thanks!

-Anders JL Beer

p.s. here are a couple lower rez movies in case anyone is having playback issues.

720p

Auto scale

p.s.s. Here is the long form version of that animation blocking with two different passes of lighting tests.

[Morbid Angel]

so which sss are you using? fast sss2 or physical sss? For fast sss2, you can increase the prepasss rate value (default -1) to 0 or 1, which will make the lightmap a lot finer and reduce the flickering. Typically when rendering moving objects with gi, you want to avoid using conventional gi interpolation methods. Its a fine balance of how much time/optimizing you can invest vs the rendering of brute force. By that I mean, if you spend 4 days trying to make the render fast by optimizing it, or send it to the farm right away with brute force and it takes 1 day to render...we typically prefer the less complicated approach and let the computers do the work for us.

[ajlbeer]

Well said about the complexity. I could not agree more, CPU's are cheaper than man hours as well

Thanks for the feedback! I am indeed using Fast SSS2 and your observations sound spot on with what I am seeing. When I get back to the office in the morning I will have a go trying your suggestions on the prepass rate.

Cheers,

-Anders