Warping effect with remove module

Hi there! I am trying to remove the overlay from a dissolved video. I am using cleanplates made in Photoshop(not using cleanplates exclusively). Right now I am removing the front of a car jumping through the air. I have had some success but I have also experienced a lot of trouble with it. I have a steady track of the background and linked it to my spline which I am trying to remove the overlay from. It looks good except I keep getting this weird “warping” motion within the removed area, and I have no idea what it is being caused by. It is a small motion but very noticeable when played back. I appreciate any help/ideas, thank you!

I’ve been experimenting with it and found out quite a bit, but have yet to solve the problem. I realized that because of the movement only happening every other frame, there was slight tracking drift every other frame, so I assumed this was the cause of the warping remove. This would make sense also because the warp also occurred on the matching frames. So to fix this I only tracked every other frame, and then the track no longer drifted every other frame (yay!). This posed another problem, though. There is still a big drift over the entire track, but I can’t fix it with adjust track without it having the same effect as a regular track would, because when I add a keyframe with adjust track, it gave tracking data to my frames that I purposely didn’t track and messed them all up like before. So, then I tried setting keyframes on the frames that I didn’t track, so they wouldn’t be affected by adjust track, but then if I used adjust track on a frame, it wouldn’t match its “match!
ing frame,” and that was pretty unsuccessful. Then I figured I would try remove on the track that drifted, w/o adjust track(at least it no longer drifted/wobbled every other frame), only to find that this drift in the track apparently was not the problem. The warp remained when the track did not even move between two frames. (I’m sending you my project file in a private message) You can see this warp in the remove between frames 229 and 230 where the frames “match,” and you can also see that it does not warp between frames 228 and 229, where the movement actually happens. This leads me to think that this is happening not because of the track drift(although that would cause it as well if present), but because the remove module is taking account for the “pixel change” in the identical frames, which is causing the warp. If you zoom in very closely on the original and examine frames 229 and 230, the movement of the image content does not change, but the pixels are different, an!
d the colors slightly change. Do you know if this is what is h!
appening
and if there is a way to get around it? Also, is there a way for me to do adjust track without messing up the frames that I purposely did not track?

Sorry for my poor terminology but I hope this makes sense! Your help is greatly appreciated, thank you!!

Thank you for your response! I don’t think it is from lens warp, and I’ve done adjust track and the problem is still there, although I think I found the source. It is a slow motion shot and only actually “moves” every pther frames. This caused some problems while tracking where it would do a fast bobbing up and down motion because the track would get semi-lost on the frames where it does not move. We got through this by only setting keyframes in a linear fashion so it would only look at the previous keyframes.

I discovered after doing adjust track that even though there is only “actual movement” every other frame, the matching frames are not actually identical because the pixels are different. I had to look very closely to really see this. I found that the warping occurs between two “matching frames,” so I’m thinking this pixel change could be the cause of it, but I’m not entirely sure. I apologize if my wording is a little off and hard to follow, I’m new to mocha and still learning!

Could I send you my project file for you to take a look at?

Thanks again! :slight_smile:

It’s probably due to a little track drift, OR it is due to a lens warp on the shot.
You will either need to solve for the lens and retrack, or use adjust track to try to fix drift.

You can send it to me to look at. It will be able to troubleshoot the shot tomorrow. :slight_smile: