Adobe AFTER EFFECTS CS3 PROFESSIONAL User Manual page 213

"Shortcuts for keyframes" on page 643
"Shortcuts for showing properties in the Timeline panel" on page 640
Interpolation methods
In layer bar mode, the appearance of a keyframe icon depends on the interpolation method you choose for the
interval between keyframes. When half of the icon is dark gray
adjacent to that side, or that its interpolation is overridden by the Hold interpolation applied to the preceding
keyframe.
By default, a keyframe uses one interpolation method, but you can apply two methods: the incoming method applies
to the property value as the current time approaches a keyframe, and the outgoing method applies to the property
value as the current time leaves a keyframe. When you set different incoming and outgoing interpolation methods,
the keyframe icon in layer bar mode changes accordingly. It displays the left half of the incoming interpolation icon
and the right half of the outgoing interpolation icon.
To toggle between keyframe icons and keyframe numbers, select Use Keyframe Icons or Use Keyframe Indices from
the Timeline panel menu.
A B
Examples of keyframe icons in Timeline panel in layer bar mode
A. Linear B. Linear in, Hold out C. Auto Bezier D. Continuous Bezier or Bezier E. Linear in, Bezier out
All interpolation methods used by After Effects are based on the Bezier interpolation method, which provides
direction handles so that you can control the transitions between keyframes. Interpolation methods that don't use
direction handles are constrained versions of Bezier interpolation and are convenient for certain tasks.
To learn more about how different interpolation methods affect temporal properties, experiment by setting up at
least three keyframes with different values for a temporal layer property—such as Opacity—and change the interpo-
lation methods as you view the value graph in Graph Editor mode in the Timeline panel.
To learn more about how different interpolation methods affect a motion path, experiment by setting up three
keyframes for a spatial property—such as Position—with different values on a motion path, and change the interpo-
lation methods as you preview the motion in the Composition panel.
Note: To change interpolation methods, right-click a keyframe, select Keyframe Interpolation from the menu that
appears, and then select an option from the Temporal Interpolation drop-down menu.
In the following descriptions of interpolation methods, the result of each method is described as if you had applied
it to all of the keyframes for a layer property. This is done to clarify the examples. In practice, you can apply any
available interpolation method to any keyframe.
See also
"About animation, keyframes, and expressions" on page 185
"Shortcuts for keyframes" on page 643
"Shortcuts for showing properties in the Timeline panel" on page 640
"Work with the Graph Editor" on page 186
C D E
, the dark half indicates that there is no keyframe
AFTER EFFECTS CS3 207
User Guide