Taken 27 years apart with high quality amateur equipment for their respective times.

Both are 30min exposures

Left hand image taken in 1984 using a Celestron 5, cold camera and HP5 B&W film, 30min exposure
See: http://www.pbase.com/strongmanmike2002/image/110766126/original

Right hand image was taken in 2011 using an Orion Optics 12" F3.8, ProLine 16803, 30min exposure
See: http://www.pbase.com/strongmanmike2002/image/135785837/original

See an animated Giff here: http://www.pbase.com/strongmanmike2002/image/140163741/original