Probalistic lights made noise that it should actually prevent

[krassi]

Hii!

i got a little question regarding the use of Probalistic lights for an animation..
i am rendering now a long interior animation with lots of cameras and i rendered a couple of hundered frames and was very confused with gigatons of noise.

i used the probalistic lights with high settings, because "they are supposed to minimize noise".... after searching for the problem (noise was in the rawlightning render pass so it was light related) and using pretty high noise and quality settings i found out that the probalistic lights caused this massiv noise in my scene..
turned it off.. render time was nearly the same, but with a clean image...


did i get anything wrong with this function or wasnt it supposed to prevent this kind of noise ?


anyway i got both lightcaches and irrandience maps with and without probalisitc lights and will try wich one is better for the final rendering, but of course without using probalisitc lights for rendering
best regards, daniel

[vlado]

The implementation in 3ds Max has some issues that we need to solve. The Maya one generally works a lot better, I hope we can do the same for Max.

However, in general, probabilistic lights do not minimize noise and I don't think I ever claimed they did. In fact, they increase noise. The hope is that passes through the image go faster so other effects like glossy reflections/GI can be interleaved with the light sampling leading to a faster rendering in the end.

Best regards,
Vlado

[krassi]

Hi Vlado!
Thanks for your lightning fast answer!

ahhhh so well i just guessed when i read in the vray manual that this should prevent noise... well i totally inceases the speed of course.. my lightcache pass right now takes 2.5 times longer but if the quality is great, i can decraese other stuff to speed up the rendering again and still get a cleaner image than before..
i will still compose the final image with rawlightning,diffuse,gi and the specular and refraction and reflaction passes in fusion with multimatte id's for every material.. so if the light ist still noisy, i can denoise it seperatly and still get a crisp lightpass using a dirtmap extra texture..

something that also helped me a lot to "fake" noiseless glossy reflections is rendering everything with 1.0 reflection rate but only 3% reflection.. the raw rendering looks dull and bad but i use the reflection pass with different blur levels and add it with the right id to every material.. this totally helped me with long interior animations that would normally take 3-5 times longer per frame .. well its not accurate but still looks good and without any noise.

its allways a miracle what comes out of Fusion after the compositing and colorgrading )


thanks for the infos Vlado!!!!
with still images it was never an issue but of course animations are a pain in the ass and every litle detail can ruin hours of work and 3000 Frames are a lot to render right now ..
Seeya, daniel!