Photographing the stars requires long exposures.  This one is 30 minutes at f/4.  The problem is that the Earth keeps turning and exposure of more than a minute or so (depending on the lens focal length) results in "streaking" of stars.  To get this shot (which is used as the background for an image in the Nudes category) I built a device called a "barn door tracker."  It consists of three pieces of wood and two hinges on adjacent sides of the center board.  The lower hinge is adjusted for elevation and the whole contraption rotated such that the upper hinge axis aligns with Earth's rotational axis.  That is, you point the hinge at the North Star.  Then the upper set of boards can be rotated with a calibrated screw.  In my case it takes a half turn every 15 seconds.  The camera is mounted on the top board and stays aligned with the stars via this process.

I don't really know any of the points of interest in this picture.  I'm really only interested in astronomy for the images!  Shot with the Olympus OM-4 and 50/1.8 lens in the summer of 2000 (about 2AM!).