CHECKING YOUR MATTES
After you’ve completed a shot, you’ll always need to go back to check whether what you’ve done, accurately isolates the focus object. You should have been trying to keep up the quality check while you were rotoing, but no matter how thorough you are, you’re always going to find areas of your matte that don’t exactly isolate to the focus object.
Changing the way you view your rotoed footage will generally bring to light inaccuracies in your matte. Every program is slightly different, but they all generally share similar ways to view your mattes:
A great way to view your mattes as a covered overlay is to create solids ...