Now I can't suggest anyone go out and do this because while I personally don't take my eyes off the road, you might be one to get distracted. Safety is always first here, I have my settings all plugged in and can change my iso and shutter speed with the dial so I'm always looking straight ahead and holding the camera out the window.
As you can imagine this does end up with a lot of unusable shots, and its not your ordinary form of composition. I can see some people being purists about it and saying that your going on luck and not skill, but I don't see it that way. The thought may have crossed my mind, but I find this as a way to pass the time and get in a lot of scenery you would not really get the same angles of.
This obviously works even better and safer if you happen to be a passenger in the car for a long trip. I suggest this method over anything else of course. You can actually time the shots your trying to get and not going so much on luck.
Now for the settings:
I'm using a canon 7d so I set my camera to no less than 2500 shutter speed. Anything less it will not freeze time from a moving vehicle. With such a fast shutter speed you are left with a couple options to get the brightness back up. Bump your iso, or goto a higher Fstop.
On a bright sunny day I usually end up with 2500 shutter, f5.6 and 400-500iso Trying to get a sunrise or a sunset is when you need to boost those numbers, and remember when your dealing with high ISO's its better to shoot a bit on the bright side, then shooting to dark and trying to bring it back. The noise will always be worse if you shoot to dark.
Finally here's some shots I've gotten while practicing, If I didn't tell you, I doubt you would guess I was driving except for the first one is kind of obvious.
That's a sample of some of my shots taken drive-by style, All these photos and many more are available as prints right from my website, or you can just go here ShiftOnePhoto.com
