User Guide

CHAPTER 6
204
Fine-tuning Animation
Hold interpolation
Hold interpolation is available only as a temporal interpolation method. Use it to change
the value of a layer property over time, but without a gradual transition. This method is
useful for strobe effects, or when you want layers to appear or disappear suddenly.
If you apply Hold temporal interpolation to all keyframes of a layer property, the value of
the first keyframe holds steady until the next keyframe, when the values change immedi-
ately. In the Value graph, the graph segment following a Hold keyframe appears as a
horizontal straight line.
Even though Hold interpolation is available only as a temporal interpolation method, the
keyframes on the motion path are visible, but they are not connected by layer-position
dots. For example, if you animate a layer’s Position property using Hold interpolation, the
layer holds at the position value of the previous keyframe until the current-time marker
reaches the next keyframe, at which point the layer disappears from the old position and
appears at the new position.
You can use Hold interpolation only for outgoing temporal interpolation (for the frames
following a keyframe). If you create a new keyframe following a Hold keyframe, the new
keyframe will use incoming Hold interpolation. See “Adjusting direction handles to create
curves and corners” on page 207.
Changing the interpolation method
You can apply and change the interpolation method for any property keyframe. Setting
different interpolation methods for different keyframes can create a more complex
appearance and add variety to your animations.
Change the interpolation method for a keyframe using the Keyframe Interpolation dialog
box, or change it directly on a Value graph or motion path. Before you use the Value graph
or motion path, note which kind of interpolation you want to change. Editing interpo-
lation on a Value graph affects only the temporal interpolation of a layer property. Editing
interpolation on a motion path affects only the spatial interpolation of a layer property.
For more information on using the Value graph, see “Controlling change through inter-
polation” on page 199.
To change an interpolation method for a keyframe using the Keyframe Interpolation dialog box:
1 In the Timeline window, select the keyframes you want to change.
UG.book Page 204 Wednesday, February 21, 2001 12:05 PM