Animating a motion tracked shot

[Angelo Lorenzo]

I have a shot of the camera tilted up to the skyline panning from left to right. I’m adding in a particle trail to resemble a plane’s contrail. This is a VFX test shot, and I know a lock off would make things much easier, but for the production we have to have a pan. It’s a Superman-ish shot.

There is obviously perspective/skew distortion and it tracks corner pin data in Mocha without a problem.

This is where I get stuck…

How do I control my particle trail with this data for best effect because I also have to keyframe the left-to-right travel as well as the perspective correction? Can anyone throw a tutorial or advice my way?

Or is there an easier way to do this?

[david bogie]

You have described an effects shot where you don’t need tracking to pull this off.
What are you tracking?
What do you think you’re going to accomplish with Mocha data in this case?

bogiesan

[Angelo Lorenzo]

I wanted to use some kind of tracking data to match the camera shake and perspective distortion, but the parallax is so great in the shot from tilting the camera up I thought using a planar tracker would produce some more useful data.

After thinking about it, I may just use the tracking data to control a camera in a precomp to get the right perspective on the contrail before inserting it into the scene. I don’t know if it’ll work but it seems logical.

I’m a cinematographer by trade, but I thought I could figure this out before we actually shoot it in two weeks… figure out our limitations.