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ADOBE AFTER EFFECTS 7.0
User Guide
384
Layer Contribution
Specifies how much the gradient layer affects the resulting fog.
See also
“About 3D layers” on page 173
ID Matte effect (Pro only)
The ID Matte effect isolates elements in a 3D channel image file. Many 3D programs tag each element in a scene with
a unique Object ID. After Effects uses this information to create a matte that excludes everything in the scene except
the element you want. Identify each object’s Object ID by applying the ID Matte effect and then clicking different
parts of the image in the Composition panel as you watch the Info panel. (You can also identify Object IDs in the
Layer panel if you select the effect from the Layer panel menu first.) If you select Object ID for the Auxiliary Channel
parameter in the Effect Controls panel, the slider automatically reflects the Object ID for each object you select. You
can isolate objects based on their Material ID, as well.
Original (left), with ID Matte applied using the near alien as the ID Selection (center), and composited over a new background (right)
Adjust the following controls for the ID Matte effect:
Aux. Channel
Specifies whether you’re isolating elements based on their Object IDs or their Material IDs.
ID Selection
Identifies the unique ID value assigned to each element in a 3D scene.
Feather
Specifies the amount of feather along the matte’s edges.
Invert
Inverts the feather.
Use Coverage
Creates a cleaner matte by decontaminating the pixels along the edge of the matte. It removes the
colors stored behind the object from these pixels. This is applicable only if your 3D channel image file contains a
coverage channel that stores information about the colors behind objects.
See also
“About 3D layers” on page 173
Audio effects
Audio effects
Audio effects add ambience to a layer, enhance or correct audio characteristics, and create special effects. You can
apply audio effects to existing audio footage or synthesize just about any sound by combining the Tone effect with
other audio effects.
Summary of Contents for AFTER EFFECTS 7.0
Page 1: ...Chapter 1 User Guide...