Tracking markers that go out of focuse on a body

Hi, Im having a very hard time trying to track some markers on a shoulder that goes out of focus about 2/3 through the clip.
The camera moves slowly towards the shoulder and after a while focuses on the head instead, making the markers more and more blurry. Im getting a track, but its very wobbly and sliding.
I havent used Mocha pro so much, but would like to know how I can make this track more stable, and if there are any tutorials out there that talks about trackers that goes out of focus.
My issues are that the markers are in a dark place, camera is moving, the shoulder is moving, the markers are out of focus after a while and its a grainy shot even though its 6k.

You can try increasing the size of the shape on the shoulder and grab a little bit of the outside edge (just a few pixels outside the edge is enough) and then you can try using adjust track to further lock down the track. If you find the track is wobbling, you can try moving to track only translation, scale, and rotation for only a few frames where you encounter problems, or you can just track translation only for problem areas, and then switch back to more parameters as you need them. And like I mentioned, you can always use adjust track to correct any drift.

It’s really important to grab large areas of texture and not focus on small markers, because Mocha is a texture tracker. But Mocha should absolutely be able to handle blur as long as your shape is large enough.

1 Like

Hi Mary,

I tried to use the adjust track, but i dont seem to do it right maybe. Ive tried a lot of trackers in the last couple of days but all of them seem to have the same problem with shaking/sliding from about half way through the shot.
(Ive put a screenshot with the beginning and end of the shot) I tried to send a reply mail with the screenshot but that was not possible. How can I send you a screenshot?
Is there anything I can do with the shot before mocha tries to track it? Ive tried sharpen, contrast, size… but no luck. The shot also has some noise in it which I remove with Neatvideo denoiser. Would that be a problem?

He is wearing a black singlet which the tracker doesnt seem to like. When I made an area that contained most of the back a little bit up from the bottom. It kept sliding down during the track. Probably because there arent much texture to track on the black fabric.

There are also shadows that moves on top of his shoulder that i tried to avoid.

The track seems to slide mostly from the bottom of the area i used (the area i mostly tried was around the markers but also a lost of the shoulder and also a bit on to his shirt). But towards the end it seems to kinda shrink instead of grow. Especially from the armpit.

Nils

You can email me at maryp at borisfx.com and I can take a look.

Thank you!!! I wasn’t having the same issue, mine was more with a face cheek with constant turns. This actually fixed mine as well.