User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
With Stencil Luma, the lighter pixels of the layer are more opaque than the darker pixels.
With Silhouette Luma, the lighter pixels of the layer are more transparent than the
darker pixels.
Stencil (left) shows all layers below through the frame of the stencil layer’s alpha
channel. Silhouette (right) cuts a hole through all layers below.
To use the stencil or silhouette modes on a layer:
1 Choose Transfer Controls from the pop-up menu at the bottom of the Timeline
window.
2 From the Mode pop-up menu for the layer you want to use as a stencil or silhouette,
choose one of the following:
• Stencil Alpha creates a stencil using the layer’s alpha channel.
• Stencil Luma creates a stencil using the layer’s luma values.
• Silhouette Alpha creates a silhouette using the layer’s alpha channel.
• Silhouette Luma creates a silhouette using the layer’s luma values.
Creating transparency using keying
You can make parts of a footage file transparent by keying out a color or luminance value.
Keying makes it easy to key objects moving across a consistent background color or objects
too complex to mask easily. When you key out a value, all pixels that have similar colors or
luminance values become transparent. This technique is often called bluescreening,
although you do not have to use blue; you can use any solid color for a background. For
information on using keying effects, see “Using keying effects” on page 278.
Note: To get more powerful keying capabilities, use the advanced keying effects available in
the Adobe After Effects Production Bundle.
UG.book Page 265 Wednesday, February 21, 2001 12:05 PM