I'm wondering if anyone here's done a stop-motion short with AS? I've done a quick test with my Macbook Pro's webcam and iPhoto, then used the IMPORT IMAGE SEQUENCE script. Pretty straightforward.
I found a great freeware/shareware app called FRAMEBYFRAME for MacOSX. Looks pretty tight. Also found a pretty good tutorial on www.stopmotionpro.com about how to set up a simple studio with a cardboard box, some transparent grease paper and a lamp for stop-motion.
Stop-motion would be possible if the onion skin function supported image files or by constantly resetting frame cycling or looping to observe the difference between the previously captured frame and the live frame about to be captured.