Mocha AE Glitch - Problem Pasting Tracking Data

[MNowicki]

Hello-

I'm running into an intermittent Mocha Glitch where the tracking data is not pasting correctly. 

In my current project, I'm using a long 90minute video with several pans and zooms between stationary shots. I've broken up the video into shorter segments of movement so I can track them individually and I put those clips into individual precomps.

After tracking the shorter clip in Mocha and confirming the track looks good, I usually return to After Effects and paste the tracking data to a Null and attach various other layers to that Null's movment. Although some of the time it seems to work fine, a lot of the clips I'm trying to track will paste glitchy odd data when pasting to a Null, solid, or any object for that matter. This happens when applying Transform and also when applying Corner Pin data to the object. Not only does the Null not match the track from Mocha causing the Null to move erradicaly all over the place, but then the keyframes have some odd spacing too.  

Here's a video that illustrates the issue I'm experiencing: Mocha Glitch

Here's an image of the keyframes not matching the track data from Mocha.

I'm on the latest version of After Effects version 22.6.0 (build 64) and all of my drivers are up-to-date.

Additional PC Specs

• CPU: Core i9-10850K @3.60 GHz
• RAM: 32GB (3200MHz)
• OS: Windows 10 Home (vesion 21H2 Build 19044.2006)
• GPU: NVIDIA RTX 3070 (driver 517.48)
• Windows 10 Home

Am I missing something? Is this a bug or is there something I'm not understanding? This seems like a simple enough task and it works majority of the time, but since it only happens intermittently 

[Jose Panadero]

It looks like an incorrect interpretation of the clip's timebase. What is the original frame rate of your clip? What is the timebase of your composition?.

[MNowicki]

I don't believe it's the frame rate issue. Everything including the comp are 59.94. See screencap below.

[Rick Gerard]

The recommended workflow for working with Mocha AE and Morcha Pro is to pre-compose moving all attributes to the new comp, then run Mocha on the pre-comp. This solves extra frames, frame interpolation, and a bunch of other problems. I never run Mocha on an original trimmed clip. I always Pre-compose then run Mocha. 

[MNowicki]

Thanks for the response, Rick.

I tried running Mocha on directly Precomp and I'm still getting the same issue. Mocha does a good job of tracking and the data looks good. But when applied to an object, the keyframes are set even more apart and the motion does not match the tracking data at all.

Here's a video of this recommended process: Mocha Glitch on Precomp

[Rick Gerard]

I don't see the surface tool turned on in Mocha. The shape can look good, but if you turn on the Surface Tool (the blue rectangle with the enter cross), you can see if the track is accurate. Without turning on this tool, there is no way to tell if a track is accurate. 

I would be willing to bet that you created a comp from a Premiere Pro sequence and that the footage in the Premiere sequence has had a time change. If you press the {} icon at the bottom left corner of the Timeline, you will probably see a speed change in the Timeline. I had this problem a while ago, and the workaround was to pre-compose the nested comp again and move all attributes to the new composition. You should also trim your null layer before you apply the tracking information.

If that does not work, you must copy and paste the keyframes to the null layer. It's a bit of a pain, but it works just fine. 

Here's a video of me solving the problem for a client a little over a year ago.

After I made the video, I found that pre-composing one more time also solved the problem.