Apple Final Cut Pro 7 - Manual (Page 78)

78 Chapter 3 Preparing Clips in the Viewer
You can add keyframes in the keyframe graph area by clicking the keyframe button for
a parameter.
Keyframe button
Keyframe navigation
buttons
If the playhead is currently on a keyframe, clicking the button removes the keyframe.
The buttons on either side of the keyframe button move the playhead forward or
backward to the next keyframe.
When keyframes are added to a clip, small diamonds appear in the keyframe graph
area to mark the location of the keyframes. You can drag these diamonds to different
positions in the keyframe graph area to change the effect.
As you add keyframes, the number of frames between two keyframes determines the
speed of a change. Hence, the more frames between two keyframes, the longer the
change takes. Keyframes that are a small number of frames apart create quick changes.