That link was pretty cool - I'd like to make some video's like that. I've made a few short ones but an hour of shooting only turns into a few seconds of video. But, to get the shots, all you need is a tripod and an intervalometer.
Ok, that explains why the lines aren't continuous and you can see that each is actually made up of smaller dots. Have you seen this?http://www.youtube.com/watch?v=pe4dpprVBGs
Thanks.
This shot is actually a 'stacked' image created from several images taken during a 1hr session. Each exposure was about 45 seconds. I used some stacking software off the web to blend them together.