you can fly!?
PD Pro Digital Painter, and Project Dogwaffle Professional:

tracking a faint star
to make it brighter
more: mo-tracking
take me back

Here's an animation created from a still image. We're zooming in, and we also wiggle the camera and it shows a lot of motion. There are a few faint stars in the back to the left of Buzz.. We want to pick one and track it, in order to make it look like a brighter star.

before tracking and changing the star
before tracking - view animation:
 AVI (765 kb) or 
Flash (new window)
after motion tracking and rendering a flare
after tracking - view animation:
 AVI (777 kb) or Flash (new window)

The default search box of the motion tracker is too large. There are more than one matching patterns  (i.e. stars) in it. As a result it can jump back and forth between two or more stars while tracking and searching for a match if we don't reduce the search area to a smaller size.

Here's the view of the keyframer after successfully tracking the star, and loading a custom brush of a flare/star.

Click the image to see the full screen capture.

It is best to reduce the size of the search box. Then there's less of a risk of  locking onto another, neighboring star.  Of course the dilemma is that if the search box is too small and the motion is too big, then the star we're trying to track might sometimes move far out of the range of the search box and get lost too. There's some experimenting needed. Sometimes you'll want to search for a larger pixel area so that it includes a pattern of more than one central stars.