The selected camera needs to have a manual mode that allows control of shutter speed, aperture (f-stop), and ISO (sensitivity). Some cameras automatic systems can handle the exposure settings or at least start the photographer in the correct direction. An accurate preview system can also be a big help in seeing what you are getting. A delay timer or a remote release is required to help eliminate camera shake. It can be surprising what you can capture even the point and shoot digital cameras. I have taken some very nice shots with my Canon A720IS.
A solid tripod or another way to stabilize a camera is required. If you try to hand hold the camera the shots will be blurry, some of the exposure times can exceed 1/10 of a second and it is a very rare person that can hand hold a camera for that long – even with image stabilization.
I will end this post with a couple of images I captured earlier this evening. Both of these were taken with my Pentax K-5 and my 55-200mm lens.