How to use tracking data for mocha mega plates in Fusion

Does anyone have a workflow to import /export tracking data for mocha mega plates in fusion ?

I use the mocha pro tracker a lot but i haven’t used the mega plate workflow yet.

I can’t work out how to get the tracking data from mocha into fusion at the correct size
… ( how to get the tracking data from mocha to put an oversized megaplate into my fusion comp)

Normally i just manually pick a surface plane in mocha to export but it doesnt work in this case because the sizes don’t match .

How do i automatically set the surface plane in mocha to match the megaplate so i can correctly export the track to fusion?

In Fusion, TBH I’m not sure how to take the relative position of a fusion corner pin to distort the full megaplate, so your only option may be to fit the surface.
I’ll check with Ben Brownlee and see if there is an easy way to do this on the comp side, as there should be a way to do a relative distortion.
In Nuke and After Effects there is such a thing as relative corner pinning, which makes it easy to warp a larger image relative to a smaller corner pin.

One way to do this in Mocha would be to create the mega plate then re-import it as an insert to your layer, then adjust the surface until it matches. If you use the right-click controls on the surface you can define the correct aspect ratio of the insert, but it doesn’t match the pixel dimensions.
We should add this pixel-matching option to make it easier to align.
The danger of doing it this way is that if there is too much planar distortion, a larger surface could break. This is why it’s preferred to do it in the comp if possible.