Tracking and PID

[ghost]

Hi, I've been looking at the kalman-filter sample and the PID controller provided by puku0x in one of the issue's. Can somebody please explain how the tracking works, I want it recognize a target (black outside, white middle) but every time i turn the tracker on, it flies to the left.

What K values are best for this and how can i fine tune it so it follows the target?

I'm excited for your answer!