Rotoscope!!
Daniel,
See Don Landis' answer… have'nt tried it, but it sounds like a great idea. We
haven't done shadows of 3D characters on top of video because we use
Premiere(Mac) to composite video actors (in bluescreen) on top of 3DStudio
backgrounds. Sounds like Don's idea'll work great.
Eric Chadwick
Mechadeus/Mondo Media