Get rid of noise with final gather!?
 

Hey,

as you can see I have some noise in my pic, rendered with Mental Ray. I've tried a bunch of settings, but I can't get rid of them. I've tried:

Anti-aliasing min,max 1,3
Filter: Mitchell
contrast threshold 0.01
max settings for raytracing
Final gather rays up to 3600
increasing the min and max radius

but still no luck (and now we're talking like 8 hours render time).

Any ideas?

hm.. I just thought of something.. maybe its my HDRI thats causing the spots. It's a sky with clouds. I'll try another one and get back to ya.

nope, that was not it. This is with a totally white environment. So anyone have any ideas which settings to fiddle with?

When I use final gather, my settings are...

Anti-aliasing min,max 1,3
Filter: triangle
Contrast threshold 0.100

Settings for Raytracing...
Reflect 2
Refract 2
Max Trace depth 4
Shadow Trace Depth 2
Scan Line-On
Faces-Both

Final Gather Rays 761
Min, Max radius 24, 240


Hope this helps out.

By the way, how are you getting the lego effect. Is it modeled, or is it a bump map?

those settings are like mine, just lower quality.. so they wont do any good...

It' modelled. A cube with a bunch of cylinders.

Do you get that with just a flat shader too? Trying to determine if it connected to the texture map or not. It looks like a photoshop cloud render to me.

The only other thing that comes to mind is a problem with face/vertex normals. But I think that would be more evident in contrast.

It's just a plain lambert...so can't be the texture.

I know that you often get noise with Final Gather, but usually you can resolve them by increasing some of the settings. But this I can't get rid of.... very annoying. Damn you MR!

Actually it was a blinn. And when I changed to lambert it rendered out fine. Also with a blinn with no hightlight, specularity and reflectivity it rendered fine. So it has to do with that obviously. I'll think I'll have a final render done tomorrow, so check the 'Finished Work' tomorrow.

I dont get this!!!!! How the !¤#*#"! could the noise show up in totally different places and different strength when rendering in different resolutions? The 320x240-render doesn't look at all as the 1600x1200? Not easy to fix this if it's random! Any ideas?

Any chance you can send me the scene file? Will try to help troubleshoot this.