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Chapter 53 Keying, Mattes, and Masks 855
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3 Move the pointer to the Canvas (the pointer turns into a crosshair pointer), then click to
change the location of the matte corner defined by Point 1.
4 Repeat steps 2 and 3 for the Point 2, Point 3, and Point 4 point controls, until you’ve
created a box that crops out everything outside the green screen surrounding the actor.
5 To round the four corners of the matte, adjust the Smooth slider, if necessary.
6 If necessary, adjust the Choke and Feather sliders.
Before changing the location
of the first point
After changing the location
of the first point
The matte, with rounded
corners