Tracking terminated prematurely Error

Hi there,

I’m running into problem tracking a pretty simple dolly shot.
Mocha tracks the scene pretty good, up until a wall slowly covers the tracked object.
I’ve tried making a Track matte but the same error keeps popping up.

Tracking terminated prematurely > One or more layers were not tracked properly,. The images are too dark or not similair enough to track.

Would anyone know a solution for this? Any help would be highly appreciated.

Screenshot:

You probably need to extend the wall shape so it overlaps more to cover the frame. Your outer shape on the frame could probably be bigger to include the corners. Also, your inner subtract shape looks a bit odd. If there are not many reflections, perhaps you do not need a subtract shape?

Another technique to solve would be to stop the track before you get the error and move the search area to include that plant on the right. It all depends on the motion, but often you can get good tracks by adding in other areas of texture that are moving on the same plane.

HTH.

Hi Ross,

Thanks a lot for your response. I tried to expand my Search shape and that seemed to work. Sadly enough I have ran into another problem. The track drifts off once it goes out of the frame.

I tried adjusting the track in the ‘AdjustTrack’ tab, and also adjusting the search shape, but the surface still drifts off… ( See screenshot)

Do you have any tips for that?

You should still be sticking onto the frame at this point. It shouldn’t drift like that until the track is almost totally offscreen.

You can use manual track for the last few frames where it goes offscreen, but you should have a better track than I see in your screenshot.

Try just tracking the right side of the image to make sure we aren’t running into an occlusion bug where shapes don’t hold out from the top of the layer pile like they should. And drag the tracking layer to the very top of your layer pile. It could be another layer is occluding this one in a way that is unhelpful.

Cheers,
Mary

Hi Mary,

Thanks. I figured to get the scene done using mattes & adjust track.

Sadly enough I ran into another problem… In the next scene te Surface track seems to drift off very slightly over time. See the screenshots below. I’ve retracked the shot multiple times using different shapes every time, but it keeps happening. I’ve also tried to make Mattes & use the Adjust Track feature, no success.

Would you know any solutions to solve this?

Adjust track should fix this. That’s what adjust track is for, correcting drift. Are you linking to the adjusted track with a new layer? If so, there’s a checkbox by link to track called “adjust” that you have to use when you link to an adjusted track.

Whenever I use AdjustTrack I just select the tracked layer. So in this instance it would be layer ‘1970’
Is that the correct way to do it?

Yes, if you’re adjusting that layer. I am asking if you’re using Link to Track once the adjust track is complete.