I have a dolly shot pushing into a character with a basketball floating below his hand. The basketball is held up by a green c-stand that we would like to key out, so we shot the exact same movement without the boy or basketball and stand to use as a plate shot.
The dolly move was made on a motion controlled rig, but we still have some shakiness to it and would like to align these two shots so it will not look.. awful.
The only thing I could come up with to this point was to track the same point in both videos, then have one of those tracking point follow the other tracking points movement. Is it possible to have a tracking point track another tracking point?
you can attach a small layer (50x50) to your tracker point and then track this one. You could also try to warp stabilize both shots. should be ok for minor shakes.
Stabilize both shots. Do the roto, lay one shot over the other so the BG plate fills the holes. Warp stabilizer won't be the best way to stabilize two dolly shots. You'll never get identical results. Instead, use Mocha. There are several tutorials available for stabilizing with Mocha.
It would really help to see the master. No need to see the clean bg plate.