Holdout masks – Apple Motion 2 User Manual
Page 871
Chapter 12
Using Shapes and Masks
871
Holdout Masks
Sometimes, while pulling a key, you lose part of the image you’re trying to keep. This
can happen when the color of the subject’s clothes is too close to the color of the
background being keyed out, or when you need to use keying values that are too
aggressive. In this example, the shadows on the elephant’s face are accidentally getting
keyed along with the background.
In these cases, you can duplicate the original object, mask the part of the subject that’s
being incorrectly keyed, and composite it over the keyed version to fill it back in.
Note: The Spill Suppression filter can modify the color of the foreground subject as
well. If you’re using the Spill Suppression filter on the keyed object, you may have to
apply the same filter to the holdout mask object to make sure the color matches.
To create a holdout mask:
1
Key and mask the foreground subject.
For more information about using Motion’s keying filters, see “
2
Duplicate the keyed object, then move it so that it appears above the original object in
the Layers tab or Timeline.
3
Mask the area of the foreground that is incorrectly keyed. Make sure that the mask is
entirely within the subject being keyed.
01112.book Page 871 Sunday, March 13, 2005 10:36 PM