I'm trying to use the Mask Path automated tracking tool to create a vignette that follows a face in a video. As all the tutorials show, it's super easy to create the mask and set up the tracking, but no matter what I do, the track falls off the face within a matter of a few dozen frames.
It's easy enough to go to the frame where the mask has drifted and adjust the mask, but those adjustments don't track forward, so when I advance to the frame subsequent to the one I've fixed, I need to entirely repeat the correction, and then all 8000 frames after... basically meaning that I'm now manually rotoscoping the footage instead of using the fancy mask track tool.
I've been searching and googling around, but don't see any tutorials on how to adjust a mask in a way that those changes track forward from a corrected frame. Is there in fact a way to track changes forward, or do I need to do this manually?