Please advice. I can't seem to find a tutorials on this subject even though i know there are many. It is most likely because i dont know the wording. I want to make a stroke or a line shape following the finger tip of my actor. So he is in front of a green screen and he swirls he's finger tip in random movements. Do i track he's finger First and then create a null? Then is it the stroke effect i use to create a path which stays on screen after he moves the finger? How can i attach an effect say i.e optical flare to follow the track points?
One last question, since following a finger tip would be a single track point i guess after effect own motion tracking is suitable but would mocha for after effects also do the job? I mean can Mocha track a single point??
Sure - mocha could track the finger and export the Transform, Scale, and Rotation keyframes. You do not "have" to use corner pin/perspective export. So this would be the same as concept as using the AE point tracker (with more robust mocha tracking).
You could use that track data for a null to drive any effect.
If you want to explore more advanced techniques, you could try 3D object tracking using either mocha AE v3 OR another application like Syntheyes or PFTRACK, etc.
Ok. Sounds great. So to do the tracking from mocha, do i just create an spline outline of the finger. Export the transform, scale, position to after effects. And will the null be in center of that tracking data?? Or how can i achieve the single Point track?