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Correcting Tracks
During tracking, if you see illumination or other small changes to the imagery causing the tracker to drift off the right spot, you can back up a few frames (to where it is still on-target), and click the Key button to re-key the search pattern. This is basically just the same as with regular supervised tracking. And similarly, you can have a key placed automatically over 10 frames or whatever, using the spinner next to the Key button.
Important : Keying is required to adapt to significant geometry and lighting changes, but too-frequent keying causes drift, where the pattern is no longer locked to the same location on the image of the pattern. An appropriate balance must be made.
When you turn the Key button on, keys are created on the unlocked joint axes, to robustly hold the object in place on that frame. The Key button overrides the joint lock buttons, making sure that the lock values are used for this particular frame. (See Keying and Hierarchies below.)
If the object has gotten more seriously off track, and can't be repaired by the backing-up approach, you can Key the frame, then adjust the Lock spinners as needed to properly position the object. Or, drag or rotate the object via its handles in the perspective view—you will be able to move it along all unlocked joint axes.
Note: if the lock spinner values are much larger than the joint minimum and maximum values (+/-100 by default), the spinner values may appear to be ignored. Increase the minimum and maximum values, accessible via the Joint/Locks dropdown.
If the frame has a notable temporary image artifact, ie it is off-track due to something visually corrupting the imagery, you'll probably want to set another key frame either on the next frame or a few frames later, so that SynthEyes knows to look for a clean frame, not one that is problematic.
Note : You can drag a GeoH object in the perspective view by its handles, but only the unlocked joints will be affected. That is so that you can reposition child objects to the right location, without affecting the (locked) joints that aren't being tracked. Changing the locked joints would mess up the overall rig. You can do that if you need to, but you have to do it intentionally.
If some portion of the shot is seriously untrackable, you can just key a frame then turn on some or all of the joint lock buttons and hand-animate that section of the shot, using the joint lock spinners.
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