I once read a great description to explain Heisenburg Uncertainty. If you want to measure the motion of a baseball you can take lots of highspeed pictures using a powerful strob-light to capture the balls position at each frame and run it together to map its motion. The photons of light, even from a powerful strob-light flashing many times per second will have no effect on the motion of the baseball. If, however, the object you want to measure is a single atom, the photons you use to measure its motion will have an effect on the motion of that atom. You could use a high intensity strob-light and hit the atom with a large number of high energy photons at once to get a very accurate position, but those photons will then drastically change the velocity and direction the atom is traveling making it impossible to plot its motion. If, on the other hand your goal is to accurately plot its motion you can try to use as few photons as possible at very low energies so that the effect on its motion is tiny, but you lose the ability to accurately measure the photon's position at any given point during its motioin.

__________________
...and we'll be saying a big hello to all intelligent life forms everywhere; and to everyone else out there, the secret is to bang the rocks together, guys...