Originally Posted by DarkSideAccord
but those shots r different from the initial guy is asking... i've done rolling shots, and those shots r easy to get.... go on a freeway and snap the pix... the difference with the pix in the 1st post is the background... rolling shots have clear backgrounds, while the other one is blurred...look at the pix below and see the difference betwen the ones in the 1st post
the pix in the 1st post is the result of slow shutter speed + movement in the car.... and no, the car doesn't need to move fast... it prob needs to move 2 feet during the 6 sec that the shutter is open...
No they don't have to move fast but they do have to move for the duration of the shutter.
First shot most likely exposed for about 1 second, note the consistency of motion in the background. A longer exposure (give or take) would have resulted in the white lights blowing out the shot and making it unuseable.
edit: the shot you posted has a fast shutter speed (note stopped background with almost no blur). My guess is 1/250 shutter speed.