X

 Soften: Use this slider to blur the keyed matte, feathering the edges by a
uniform amount.
 Erode: Drag this slider right to gradually increase transparency from the edge of the
solid portion of the key inward.
4 Click Spill Suppression to reveal the following controls:
 Spill Contrast: Use this grayscale gradient to adjust the contrast of the color being
suppressed, using Black and White point handles (and corresponding sliders).
Modifying spill contrast can reduce the gray fringing surrounding a foreground
subject. The Black point handle (on the left side of the gradient control) lightens
edge fringing that is too dark for a successful composite. The White point handle
(on the right side of the gradient control) darkens edge fringing that is too light.
Depending on how much spill is neutralized by the Spill Level slider, these controls
may have a greater or lesser eect on the subject.
 Black, White: Click the disclosure triangle in the Spill Contrast row to reveal sliders for
the Black and White point parameters. These sliders, which mirror the settings of the
Spill Contrast handles described above, allow you to keyframe the Black point and
White point parameters (via the Add Keyframe button to the right of each slider).
 Tint: Use this slider to restore the natural color of the keyed foreground subject.
Because the Spill Suppression controls eliminate blue or green spill by desaturating
subtle blue or green fringing and reection on the subject, the Tint slider lets you
add hues to restore the natural color of the subject. Overdoing this parameter
results in over-tinting the subject with the complementary color of the hue being
suppressed—magenta if green, and orange if blue.
 Saturation: Use this slider to alter the range of hues introduced by the Tint slider
(when the Tint slider is used at moderate levels).
392 Chapter 12 Keyingandcompositing