I think some clarification is warranted
A Tracker has a Reference Frame. If you set the Reference in Match Move Settings (Operation tab) to "Select Time," this is the frame on which the playhead was sitting when you hit one of the Track buttons for the first time. Otherwise, by default it will be the first frame of your composition. At this frame, the transforms the Tracker will output are all zeroes, meaning that the image you apply the tracking data to will remain in its position at that frame.
The simple solution to this problem is to set Reference to Selecct Time and start your tracking at the same frame which you froze. But if you've already done the tracking, or if you need to apply the same data to more than one element that you've frozen at different points in time, then you need a way to update the Reference Frame.
The slightly more complex, but much more flexible, solution is to download TrackerPlus from Reactor, which includes a tool script called "Set Current Time as Reference Frame." Access it by right-clicking the Tracker node, and going to Script > Tracker > Set Current Time... (And in the future, use the TrackerPlus macro you just downloaded in place of the regular Tracker, as it has the script built-in, plus additional scripts to track forward and backward by just one frame at a time.)
This script will change a couple of hidden parameters in the Tracker to set the Reference Frame to the current playhead time. In the case where you need multiple Reference Frames, you'll need to duplicate the Tracker for each additional freeze frame and run the script on each of them at the appropriate frame.
I prefer to set my Trackers to FG Only and use a separate Merge node to add each element in order to reduce confusion.
- Capture.JPG (471.07 KiB) Viewed 882 times
I'd attach the comp itself, but trackers make it too big (and I didn't actually do the work on frame 27 anyway
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