Hi, I’ve a little problem with the Vector blur filter. It seem to me that whenever I have two or more moving faces in front of eachother the hinders blur will render in front of the surface in front of it. :spin::spin::spin::spin:
After ours of searching for the cause I’m out of luck and hope anyone can help me :).
Here is a .blend illustrating the problem: untitled.blend (552 KB)
Render at frame 2 and you’ll see what I mean.
When you add vector based blur to rendered image, most vector blur filters don’t know/use the spatial layout of objects. There is no way to tell which surface is in front, so blur can be unrealistic. It is just the “bonus” that you receive when you push this effect to compositing stage.
You could make it work better if you separate the conflicting objects to separate render layers, apply blur separately and combine them in the end.
I seriously doubt it’s a bug. The z-pass tells the depth of a pixel but without what’s behind, vector blur doesn’t have data to blur. Keep in mind that vector blur is an image processor: If the image doesn’t hold the data, it can’t extract it from the scene.