Mocha unable to latch onto track

Hello everyone,
I have a shot from a documentary where one of the interviewees is clearly waving a joint in the air. The directors came to me to save the shot and I thought it would be a relatively simple track in Mocha, but the program is having trouble holding onto something to track.
The shot is interlaced HDV footage in dim light (ie noisy) so I tried fixing the colors and bumping the contrast in AE before bringing it back to Mocha but with little success. The area itself might be too small to track so I tried tracking the hand, but that takes it all over the place.
Below is the original footage.
http://www.mediafire.com/?cu0atyfpe5jpovx
Any suggestions would be much appreciated.

Hi There,
There’s a few things that might save this (in order or trying it out):

  1. Have you tried using auto channel?
  2. Have you tried tracking translation only?
  3. Have you tried upping the percentage of pixels tracked up to 100%?
  4. Have you increased the angle% or the scale% that mocha is looking for in the shot?
    Those changes might help you get a better track, without seeing what is going on in the shot.
    Cheers,
    Mary

thanks for the help, Mary. You’re right, I think I have to take it on with a paint brush, one frame at a time… I wish that guy would just pass it on and get it out of the shot.