The older pictures going back to 2003 were taken with a Nikon CoolPic 4500, by today's standards, that was a very noisy, slow chip.
Moved on to the Canon 10D which was a great leap forward, but again, by today's standards, that was still a fairly noisy, slow chip.
As of Dec 2014 I now have a Canon Rebel SL1 and picture quality should improve.
Below is link to great video done by Chris Cook showing what doing the "outside" part of astrophotography is about.
There is lots of imaging processing done on the "inside" later.
It is 4 hours compressed into just over 1 minute. Telescope is an Astro-Physics 130EDT, target is the Swan Nebula M17.
The Milky Way is seen gracing the southern sky with Mars showing up towards the end, at bottem right.
Link to YouTube video
Chart showing star magnitudes