Thanks Rick, Rob, niko, Darren & Petra.
The 650 images i used was for a timelapse i did, then i realized i could do a startrail with them.
Loaded all the images into the program http://www.startrails.de/html/software.html and let it do the work.
It used to be so easy with film, you just stopped the lens down and left the shutter open forever. I haven't tried it with digital yet, I'm now inspired to give it a shot.