Keyframing the PI emitter offset?

Host is Vegas Pro 17-452

I feel like the core of my question might be for the Mocha team but since I’m using this from within Continuum, I thought I’d start my question here.

I’m tracking a fairly simple subject in order to apply a PI effect. The camera isn’t moving (in this project at least) and there are a few spots in the footage where tracking falls down. Based on roto that I’ve done I expected to be able to add keyframes to these areas to help tracking.

Unfortunately the emitter offset doesn’t appear to be stored with keyframes.

Here’s a video showing the issues I’ve seen. I’m wondering if they’re bugs or if I’m misunderstanding how PI fx are intended to work with mocha.

In summary, the issues I’m running into are:

  1. EO appears to be locked relative to the search area’s last tracking position?
  2. EO isn’t stored with keyframes.
  3. When tracking is lost, the EO jumps a couple of frames back.
  4. Keyframes aren’t automatically generated unless there’s at least one manual keyframe.

Hi Michael,

If you can send me the footage I’d be happy to give it a shot and work with you to achieve the desired result. You can send that to me privately at


@PeterMcAuley Done and thanks.

@michaelh I wonder if this Mocha tutorial will help? It’s Mocha Pro but perhaps it will explain how to add manual tracking into an auto track (at about the 4:00 mark if you’re impatient, but I recommend watching the whole tutorial as it gives other tips and explanations).


@Alan_Lorence Unfortunately the manual tracking is part of what’s “broken” with PI emitter tracking. I understand from @PeterMcAuley that it’s not so much broken as it was a design decision with regard to emitter tracking. He was able to get me the info I needed to move forward and the key was to mostly abandon the idea of doing anything with the emitter position within mocha. Rather, get a good track using the emitter search area and then keyframe the emitter offset parameters within the host to get the final position set. That’s more fiddley than I would prefer but workable, certainly for short clips. Likely just fine for longer ones that are properly planned and shot for tracking

The video you posted was very informative, much like all your tutorials, so while I didn’t get info I could apply to my current tests, it has made me want to purchase mocha pro even more than I did before. So, good job! :slight_smile:

While going through the steps Peter supplied, I had a request from a friend for people to create a short “happy birthday” clip for his wife. Using those techniques, here’s a clip I whipped together and submitted.

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Glad to hear that worked out for you Michael. And that’s a pretty funny birthday card!! :slight_smile: