I have a problem, I’m rendering an animation and I realized that full sample sometimes leaves some ugly magenta artifacts (that become even uglier after defocus). Here are two samples, one with full sample rendering and the same picture without it. Is there any way to solve it?
First thing what comes to mind is this field…
I would have gone over my textures and switched this to another terrible one
Of course this could be something more tricky to find.
Those look like the kind of artifacts you get from using the wrong premultiply settings. How is the scene set up? Are you using any alpha-over, or similar compositing effects ?
One material with some reflectivity in the text (not the problem, I rendered it shadeless and the same issue happened).
Lights are made of two materials: an internal shape with an emit (I use indirect lightning but it also happens with it off) and another external shape simulating glass.
There are also some thousands of particles.
All materials are simple, no textures used on any of them. And I attached my node composition…
Color Unpremultiply option for images and render settings. For premultiplied alpha images, this makes any color space conversion for the image or render output work on color without alpha multiplied in. This is typically useful to avoid fringing when the image was or will be composited over a light background. If the image will be composited over a black background on the other hand, leaving this option off will give correct results.
Are you on a build with this option? Just a thought…
Oops, I talked too soon. The problem persists (I was rendering a wrong version of my animation). But at least I know what happens now…
Blender has problems with Full Sample when the edge of an halo material coincides with the edge of a mesh. Apparently it’s a bug. I have already reported it. Thanks anyway to all!