by Kariudo » Sat Apr 21, 2007 3:22 pm
make a black circle on a white background in mspaint (might be the other way around...in which case you just use invert colors in mspaint) and save it.
open up premiere, look for the image matte key effect (or image mask transition), browse for your image.
I'm using pro 1.5, so the effect/transition names might be different