I took these photos last night with my Nikon D5000. I set it to take repeated 30 second exposures. I then overlaid the images using a command line bash script and Image Magick. The first is about 25 minutes worth of photos, the second is about 50 minutes worth.
[singlepic id=2045 w=500 h=300 float=center]
[singlepic id=2044 w=500 h=300 float=center]
I started with a the first image as the “../temp.jpg” as listed below. This could be a image from the series or a blank black image of the same size. Then I ran the bash code below to generate the images.
$ ls *.jpg | while read a; do convert ../temp.jpg $a -gravity center -compose lighten -composite -format jpg ../temp.jpg; done;
