So I'm trying to track a panning footage(start in center, pan left, pan right without stopping in the middle, and back to center.), and I want to place the tracker in the end where there is no motion blur and track backwards to get a more accurate result, but every time I try to track it won't even do one frame without losing the target while it is clear to see. What should I do?
TL;DR Cannot track backwards without losing the target while it is clear.
Read:
How can I get better results when doing camera motion tracking?
and
Some Data Failed to Reconstruct, Motion Tracking
If there is motion blur or your footage is blurry, it is very unlikely that you will get accurate tracking regardless if you are tracking backwards or forward.
Things you can try:
Make the search area for the tracker larger
(if the search boundbox is not visible enable it on the marker display section)
Use a different tracking preset:
Prefetch the clip (to prevent errors when decompressing the video frames)
Set the Motion model to Affine or Perspective
Use Match: Previous Frame instead of keyframe.
Enable Prepass and Normalize.
Note that there is a chance that you might encounter errors tracking backwards if your video is encoded using Long Group of Pictures (GOP) encoding and not intra-frame encoding (look that up on your favorite search engine). Blender has issues reading backwards or dealing with video encoded with variable frame rates. In that case you would need to re-encode the video before tracking, or convert it to an image sequence before loading it to blender.
Read:
https://blender.stackexchange.com/a/8635/1853
and
Why is tracking getting less accurate after going past cached frames?