I’m rendering a 3D object to be composited over video. Mblur looks very good, but I can’t stomach the rendering time. I setup a Vector Blur node but discovered a problem. When I render it with premul, the blur effect is only visible over the object itself, but not beyond its limits. In other words, the object’s surface looks smeared, but not past it’s edges. There is no blur trailing the object.
It looks like vector blur is not functioning in the alpha channel. Is this a limitation of the vector blur, or is there a way to make it work?
I can post an example if my description isn’t making sense.