Tracking difficult and fast panning shots with Mocha for stabilization.

[Ross Shain]

It appears from your video that you do not fully grasp the concept of “planar tracking”. Are you sure you have watched the mocha getting started videos? https://www.imagineersystems.com/mocha_Fundamentals

Regardless, if you are trying to stabilize, roto or simply do a match move, the mocha user needs view the shot and think about planes.

You created a shape around the entire car, flag and person. These areas are not all moving on the same relative plane. What I would recommend is creating a shape for the hood of the car, one for the side, one for the window. Each spline has its own “surface” which is the blue box that represents the tracked plane.

Once you track, view the surface. If the track on the surface is not very good, the spline will not follow well. If your track is not very good, and you are animating the spline, there could be a counter-intuitive battle going on. Splines are linked (children) of the tracked surface.

I hope this helps. You can always contact Imagineer support for more detailed help.
https://www.imagineersystems.com/contact_form

Ross Shain
Imagineer Systems
http://www.imagineersystems.com

[John Mayer]

Hello Ross, thanks for your answer, and yes this is helping me a lot.

I indeed watched these basics, but I got lost in complexity of some of it so I never totally grasped the planar tracking. Fortunately your last explanation had made me realizing a couple of misconception what Mocha doing and thanks for pointing me out the wrongs. I’m still questioning myself about planar tracking for really rough rotoscoping that shouldn’t need complex plannar calculation like my example above. Regardless of your suggestions it couldn’t make a difference in better tracking until I crank up the search area. So I’ll leave this for now since I have moved since.

Very appreciated!

[John Mayer]

Right now my biggest pet peeve is to track a target that get hidden completely by an obstacle during tracking, mostly composed by crowds. I tried to roto the obstacle and put in foreground but it doesn’t work as the target get completely lost in tracking once they enter the obstacle. I haven’t see a remotely close tutorial in order to counter the problem. I was hoping to manually create some ‘prediction’ frames with adjust tracking and manual tracking but you can’t move all the corner pins at once as far as I see. The only workaround which work best for now is to track the out between tracking before and after the obstacle and export the tracking datas in AE and handle the missing tracking with a couple of Nulls to compensate.