Mocha Tracking a Tire - Suggestions?

I’ve got a straight on shot of a tire spinning that I need to track and place a logo on the outer rim of the tire.

What I’m using is Mocha for AE (v2) to get the track, as that seems to be the best solution. The footage was shot on a 5D Mark II at a relatively high shutter speed of 160, and each frame is crisp. The tire is going at precisely 33 rpm, like a record. When I’m tracking the footage it works decently, but mocha doesn’t like using only translation and rotation when doing the track, it loses it completely. Only when using every option, including perspective, does it get a fairly decent track, but it’s not perfect.

I’d like to get a solid track with a minimum amount of adjustments, as I need about 30 seconds worth of the footage for the composite.

Any suggestions on tracking a constantly spinning plane in Mocha?

Have you tried increasing the “Angle” setting in search area? By default mocha will track small amounts of rotation, but if that’s the dominant motion and the surface is spinning quite quickly, then you should increase this.

The value is specified in degrees, assuming you ran the 5D at 30 fps, then for a 33-rpm surface that’s 6.6 degrees per frame. Try 10 and see if you start getting better results.

J-P

Without seeing the footage, it is very difficult to make recomendations here.
Perhaps if there is something else in the shot (like the bumper or rims) on the same plane, this could help the track better. Also you might want to try “excluding” the center of the tire by adding a shape to that layer (subtracting the center) and tracking just the edges. The rotations could be throwing the track off as well.

-R

—Quote (Originally by Andrew Spirk)—
I’ve got a straight on shot of a tire spinning that I need to track and place a logo on the outer rim of the tire.

What I’m using is Mocha for AE (v2) to get the track, as that seems to be the best solution. The footage was shot on a 5D Mark II at a relatively high shutter speed of 160, and each frame is crisp. The tire is going at precisely 33 rpm, like a record. When I’m tracking the footage it works decently, but mocha doesn’t like using only translation and rotation when doing the track, it loses it completely. Only when using every option, including perspective, does it get a fairly decent track, but it’s not perfect.

I’d like to get a solid track with a minimum amount of adjustments, as I need about 30 seconds worth of the footage for the composite.

Any suggestions on tracking a constantly spinning plane in Mocha?
—End Quote—