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Chapter 2 Motion Tracking 83
Finding a Good Reference Pattern
The first step in selecting a good reference pattern is to play the footage several times.
As you review the clip, try to locate a reference pattern that follows as many of the
following rules as possible:
 The pattern ontains perpendicular edges, such as dots, intersections, and corners
(lines and straight boundaries should be avoided as tracking reference patterns).
 It is a high-contrast pattern.
 It contains even changes in brightness or color (an example of an uneven color or
brightness change is a sharp-edged shadow that passes over your reference pattern).
 It appears in every frame of the clip (does not move offscreen or become obscured
by other objects).
 It is distinct from other patterns in the same “neighborhood” in the clip.
Manually Coaxing Your Track
Another technique you can use is to manually insert tracking keyframes. For example, if
you have 100 frames to track, you can manually create a keyframe every 10 frames.
To manually create tracking keyframes using the Record button:
1 Enable Record (press A).
2 In the Canvas, position the tracker at the reference point you want to track.
A tracking keyframe is created in the behavior.
Note: You can press Shift-Period to jump forward 10 frames, or press Shift-Comma to
jump backward 10 frames.
3 Repeat step 2 until you’ve completed the track.
To manually create keyframes without enabling Record:
1 In the Canvas, position the tracker at the reference point you want to track.
2 Do one of the following:
 For Analyze Motion, Match Move, or Stabilize (with manual trackers), choose
Object > Add Position Keyframe or Object > Add Result Keyframe (or press
Control-K).
 For Stabilize (automatic mode), choose Object > Add Motion Vector Keyframe.
Manually Modifying Tracks
You can manually modify track points.
To manually adjust an onscreen track point:
1 Position the playhead at the frame you want to modify.
The track point at the current playhead position is highlighted.