Apple Final Cut Pro 7 - Manual (Page 1109)

5 In the Current Timecode field of the Motion tab, enter “01:00:02:00” to move the playhead.
Entering the new
timecode value
moves the playhead
to this location.
6 Click the keyframe button for the Opacity parameter to create a keyframe at the new
position of the playhead.
Because it takes at least two keyframes to create a dynamic change to a parameter over
time, you’ll need to add another keyframe.
7 Move the playhead to 01:00:03:00 on the keyframe graph ruler, then create another
keyframe.
A second keyframe is
added to the Opacity
keyframe graph line.
1109 Chapter 67 Adjusting Parameters for Keyframed Effects