User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
Luma Inverted Matte Opaque when a pixel’s luminance value is 0%.
After Effects converts the next layer above into a track matte, turns off the video of the
track matte layer, and adds a track matte icon ( ) next to the track matte layer’s name in
the Timeline window. The Composition window displays the fill layer viewed through the
alpha channel of the matte layer.
Note: Although the video is turned off for the matte layer, you can still select the layer to
reposition, scale, or rotate it. Select the layer in the Timeline window, and then drag the center
(indicated by a circle with an X) of the layer in the Composition window.
Preserving underlying transparency during compositing
The Preserve Underlying Transparency option specifies that the opaque areas of a layer
display only when positioned over opaque areas in underlying layers. With this option,
you can make a layer display only when it is positioned over the layer below it. It’s useful
for creating effects such as glints or light reflecting off a polished surface.
To preserve underlying transparency:
Select the T option in the Layer Switches column for the appropriate layer.
Using layer modes
Layer modes control how each layer blends with or reacts to layers beneath it. The stencil
and silhouette layer modes affect the alpha channels of layers beneath them. Other layer
modes affect how colors appear when blended with the colors from other layers. Layer
modes in After Effects are identical to layer modes in Adobe Photoshop.
UG.book Page 261 Wednesday, February 21, 2001 12:05 PM