Apple Final Cut Express HD - Manual (Page 815)

Chapter 55 Keying, Mattes, and Masks 815
IX
 Select Color button (the eyedropper): When you click this button, the pointer turns
into an eyedropper you can use to select a color from a clip in the Video tab of the
Viewer or in the Canvas.
Clicking this button, and then Shift-clicking with the eyedropper in the Viewer or
Canvas, allows you to select another region of the background screen that wasn’t
keyed out by your first use of this control. This broadens the range of colors to be
keyed out and enlarges the keyed-out area. You can do this repeatedly to broaden
the range of keyed-out color to include shadows or highlights on the background
screen, if necessary.
 View Final/Matte/Source button (the key): This button has three states:
 The default state (a gold key against a gray background) lets you see the end
result, the effect happening within the keyed area.
 The second state (a black key against a white background) displays the key itself as
a grayscale image, so you can fine-tune it without being distracted by the image.
 The third state (a gold key against a blue background) shows only the original
video image.
 Invert Selection button: Click this button to invert the key you’ve defined. For
example, suppose you’ve set up a key based on the color of a green car and turned
the desaturation all the way down so that the car is grayscale and the background is
color. Clicking the Invert Selection button makes the background grayscale, and the
car appears in color.
 Edge Thin slider: Drag this slider to make the size of the currently defined key larger
or smaller. This can help you remove unwanted edging around your subject.
 Softening slider: Use this slider to blur the edges of your key to make it blend better
with the background image. This can come in handy to soften the jagged edges that
sometimes develop when chroma keying material captured with the DV codec.
 Enhance slider: Adjust this slider to selectively eliminate any spill of the key color that
may be visible in the semitranslucent areas of your key, such as edges and holes.
Three sliders at the bottom of
the Chroma Keyer let you make
further adjustments.