Of note for newbies (like me) who are somewhat scientifically challenged. This won't work from a moving car--finally figured out that I am going the same speed as the other cars which cancels out everything else. Also of note, it really bugs other drivers to have you panning and snapping at them and could cause an accident as they glare back at you over their shoulder. Ahem. Unfortunately, end result of 29 tries is not one focussed subject with blurred background. Next attempt will be to corral 5 year old and force him to run in front of camera over and over and over until one of us drops from exhaustion. No bets on who will drop first.