ADOBE PREMIERE PRO 2.0
User Guide
361
See also
“About keying” on page 355
About the Color Key
The Color Key effect keys out all image pixels that are similar to a specified key color. This effect modifies only the
alpha channel of a layer.
When you key out a color value in a clip, that color or range of colors becomes transparent for the entire clip. Control
the range of transparent colors by adjusting the tolerance level. You can also feather the edges of the transparent area
to create a smooth transition between the transparent and opaque areas.
See also
“About keying” on page 355
To key out a single color
1
Select a clip in the Timeline panel.
2
Apply the Color Key effect to the clip.
3
In the Effect Controls panel, click the triangle to expand the Color Key effect.
4
Do one of the following to specify the key color:
•
Click the Key Color swatch to open the Adobe Color Picker, select a color, and then click OK.
•
Click the Eyedropper icon, and then click a color on the computer screen.
5
Drag the Color Tolerance slider to specify the range of color to key out. Lower values key out a smaller range of
colors near the key color. Higher values key out a wider range of color.
6
Drag the Edge Thin slider to adjust the width of the keyed area’s border. Positive values enlarge the mask,
increasing the transparent area. Negative values shrink the mask, decreasing the transparent area.
7
Drag the Edge Feather slider to specify the softness of the edge. Higher values create a softer edge but take longer
to render.
Using the RGB Difference Key
The RGB Difference Key is a simpler version of the Chroma Key. It lets you select a range for the target color, but you
cannot blend the image or adjust transparency in grays. Use the RGB Difference Key for a scene that is brightly lit
and contains no shadows, or for rough cuts that don’t require fine adjustments.
Note:
The Difference Matte Key uses a matte to define the alpha channel much as the RGB Difference Key uses a color.
For more information, see “Difference Matte Key effect” on page 318.
The following RGB Difference Key settings are adjusted in the Effect Controls panel:
Color
Specifies the color in the video that will be made transparent by the mask.
Similarity
Broadens or reduces the range of the target color that will be made transparent. Higher values increase
the range.
Smoothing
Specifies the amount of anti-aliasing (softening) that Adobe Premiere Pro applies to the boundary
between transparent and opaque regions. Choose None to produce sharp edges, with no anti-aliasing. This option is
useful when you want to preserve sharp lines, such as those in titles. Choose Low or High to produce different
amounts of smoothing.