There is another way, following on from Russell's post. You don't need a goto mount, but it means the use of an equatorial platform in order to track.
There are many people who use equatorial platforms successfully, including dobs upto 30" in size.
I recently used an eq platform with my 8" f/4 dob.
Most platforms are made for visual use, so there is some lag & backlash with the gear meshing, which for visual is no problem, but for photo it can be a pain in the neck. There are some autoguided platforms being developed too. In the end it comes down to how much you want to spend. No photo solution in astronomy is without cost.
I won't double up on the background info on the photos below as you'll find it all in the "Video Astronomy" sticky in title page of this equipment forum. Photo is not my main focus in astro, and video astronomy suits me just fine. There are some exponents of VA who are really hardcore about it, and get incredible results. VA is not the only way of achieving photos with a dob. The main things to think about with a dob, whichever way you go, is keeping the scope balanced as some cameras can be very heavy (DSLRs). Other cameras that can be used are the humble webcam that can be modified to become excellent planetary cameras. There is an article here in IIS on webcam modification, and how to process the images using 'normal' astro software. It's one relatively inexpensive way to start dabbling in astrophotography,
The article is this one:
http://www.iceinspace.com.au/63-431-0-0-1-0.html
Alex.