Animating with the HUD
Parameters that appear in the HUD can be keyframed using the Record button or by
setting an initial keyframe. For example, when an object is selected in the Canvas, the
HUD gives quick access to the object’s opacity. To make a custom effect such as a
temporary dip to black, keyframe the opacity parameter in the HUD.
To animate a clip’s opacity
1
Place the playhead where you want to begin the fade.
2
Do one of the following:
• Click the Record button (or press A) to turn on keyframe recording, then click the
Opacity slider handle in the HUD.
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Even if you don’t change the slider’s value, clicking it sets an Opacity keyframe at that
point. This way, the object remains at its previous opacity from the beginning of the
clip until that keyframe, then begins the interpolation toward the next keyframe.
• With the Record button off, click the Opacity slider handle in the HUD, then press
Control-K.
3
Move the playhead forward to a new time.
4
Change the Opacity value.
5
Move the playhead forward again.
6
Change the Opacity slider again.
7
If keyframe recording is on, click the Record button (or press A) to turn off keyframe
recording.
Keyframes at the Beginning and End of the Curve
When you begin adding keyframes, you instruct Motion to modify the in-between frames
to interpolate the effect. But what values are used for the frames before the first keyframe
and after the last one?
By default, when you add your first keyframe, that same value is extended forward and
backward to the beginning and end of the clip (as if you hadn’t added a keyframe).
After you add a second keyframe, the effect begins to change over time. The frames
before that first keyframe remain at the value of that first keyframe. Similarly, the frames
after the last keyframe hold at that last defined value.
You can override this default behavior to create loops and other patterns by using the
Before First Keyframe and After Last Keyframe submenus as described in the
Extrapolation
section later in this chapter.
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