I’ve done this before, so I thought I’d try again.
It’s really quite easy to do (even more so in a car the size of mine), but the effects are simply stunning.
These were all shot with the posted 30mph speed limit (probably a bit slower than that), and are 13 second exposures.
I stood the tripod in the back of the car, with a leg wedged in to the seat fold, focused to infinity and used my remote sequence timer to activate the shutter. This meant that at no time while I was driving, did I have to touch the camera to activate it