I have a feeling this has been asked before, but my search didn't turn it up:
I have a a "reflection" that I'm masking with a black and white (straight?) alpha layer--it's working great, until I enable motion blur, then things get a bit out of alignment
is there a trick to getting the motion blur to effect my mat in the same way it is affecting the rest of my assets?
(for reference, there are a couple images, the first showing the "reflection" layer that's just a bit off, and my alpha mat in the second)
Stock AE answer no. 1: Pre-compose - that is the matte and color before introducing motion. Which order makes sense and how many duplicates/ instances of your pre-comps you ned you will simply have to figure out as you go along.