Apple Final Cut Pro 7 - Manual (Page 1239)

7 Depending on how the edges of your foreground subject look, you may want to make
adjustments using the Edge Thin slider. The Edge Thin slider allows you to shrink the
alpha channel created by the Chroma Keyer to begin to eliminate the light fringing that
remains around the edges of the foreground subject.
Before adjusting
the Edge Thin slider
After dragging the
Edge Thin slider to
the right
8 An optional step at this point is to use the Softening slider to blur the edges of the
foreground subject. This is especially helpful if the edges of your foreground subject look
rough because of compression artifacts that appear as blocky edges around your
foreground subject. Don’t overdo this adjustment, as you could start to lose details in the
subject that you’re trying to preserve.
Before adjusting the
Softening slider After dragging the Softening slider
slightly to the right
1239 Chapter 72 Keying, Mattes, and Masks