hi drummer grl,
I'd go with Cranston's approach, I've got a couple of transparent .png's that are 'ruler' marked' with a marked out centre scale, corners and diagonals. I use them in a PiP track as temporary guides for positioning.
It's really difficult to line PiPs up as even a pixel width gives that little change with still images. Dafydd's matrix PiPs are really useful for positioning but your use of motion makes matching the original image to the motion end point difficult.
Cheers
Adrian
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