Import tracking data to AE problem

Hi,

I am still relatively new to AE and even newer to Mocha so here goes a potentially silly question/ problem. Please bare with me.

I have some shaky footage and need to track an object so I can “attach” some FX to it in AE (A particle emitter to be exact) I would like these FX to follow the object I have tracked as the camera shakes around.

Mocha does a great job of the tracking part; I tracked the object using the x spline layer tool and the track is PERFECT. (Just to be sure I inserted the Mocha logo and viewed the surface and grid and they all stay beautifully stuck to the object I need to be tracked.)

I export the transform data to AE and attach the data to a null object.

I then delete the Anchor keyframes and reset it.

Then I parent my FX layer to the null object and line up the FX to where they need to be.

Heres what happens:

On the first frame the null object/FX layer lines up perfectly … but then it drifts WAY off to the left before gradually coming back to the proper position on the last keyframe.

I have tried applying the tracked data to null objects, solids, directly to the FX track and I even pickwhipped the null objects’ position to the emitter position and they all have the same result: First and last frames are ok but everything in between is just ghastly.:frowning:

I am wondering why, if the track I have made in Mocha appears to be so spot-on, when I try to use the data in AE it gets all “wonky”.

It looks like scale might be an issue here. As the shot zooms the null object/FX layer goes off track almost as if its scaling from a different position than that of the track data.

The clip is shot at 10fps and I have made sure mocha is set the same. I also make sure to paste the data in AE on the same frame as I started the track (in this case frame 1).

Sorry for the length.

Any help would be greatly appreciated.:slight_smile:

Thanks

-Trevor

A few thoughts…

Pixel aspect ratio. Has to match for both AE and mocha.

If you use the track data for a simple solid, does it line up?

If the tracking in mocha is spot on , than the issue is usually the comp settings in AE, how you are interpreting the source footage in AE OR something related to the layer sizes.

If you want to post me your projects, I can take a look.

-Ross

rosss@imagineersystems.com

Thanks Ross,

True enough it was the pixel aspect.

Mocha did a great job of interprating the footage (fpm, ect) but AE had comped the footage as NTSC while Mocha was set to HD (default?).

Anyway after changing the settings in Mocha to match AE’s settings and smacking myself in the head the track came out beautifully.

Thanks again.

-Trevor