artifacts in vray paint when rendering animation

[stevesideas]

I've pre-calculated the lightcache and then the irr map for an animation where only the camera is moving. I used the standard method of creating the cache files. Lightcache for glossy rays is not on.

For some reason I'm getting artefacts in the paintwork on one of the cars when I render.

Any ideas how to resolve this ?

[jacksc02]

I am guessing it renders cleanly when you render with single frame GI?

[stevesideas]

Yes. When not using the cache files everything is fine. I am now trying to re-calc the cache files with "lightcache for glossy rays" on. This might help.

[jacksc02]

It looks more like IRmap artifacts rather than Light Cache.

[stevesideas]

Possibly...not sure what I could change to get rid of them. I did have a problem with similar artefacts in refractive materials once and Vlado recommended turning on lightcache for glossy rays hence the reason I tried this out.

[stevesideas]

okay. It is definitely the irr map. I switched to just using the lightcache and the image is clean...im wondering if doing it this way might be the best way to go...lightcache for both first and secondary gi ?

[jacksc02]

Steve,
Irmap should be fine.
What settings are you using?

[stevesideas]

medium animation settings. Hsph: 60 Int samples: 20

Use camera path.

[vlado]

Check for double faces or inverted normals; we had a similar issue in a scene where the smooth surface normals were in the opposite direction to the geometric normals. This seems to be a common problem with CAD meshes.

Best regards,
Vlado