The hobby of digital astrophotography has streaked ahead in leaps and bounds over the past few years and amateur astronomers all have their own preferences on which type of camera to use.
One of the major benefits of a DSLR is that being a multi-purpose camera it can be used for ordinary terrestrial photography as well.
It's true to say that even the most basic models on the market with an 18-55mm lens will have a large enough field of view to cover vast areas of our Galaxy and are capable of producing stunning images.
Of course it's great if dedicated lenses can be used, as these will provide superior shots but do come at a cost, and maybe out of the price range of many people.
The most popular digital cameras for astrophotograpy seem to be Canon and Nikon, and there is video below with the pros and cons of the Canon EOS Rebel T2i . The video goes into a lot of detail about the various functions on offer and what kind of results you can expect.
There are other models in the Canon range that have now been discontinued but are very good, and you have a good chance of being able to pick one up at a bargain price as astro photographers upgrade their equipment. As with all digital cameras they will require a T ring for astrophotography.
You may already be aware that digital noise can be a common problem, which, must be corrected if you want the best images possible. This is particularly true if you intend to do long exposure imaging. A professional digital camera conversion will help to eliminate this problem.
Before you begin your outdoor photo shoot you should ensure your batteries are upto it, as a cold evening will exhaust them rapidly.
You will need to experiment with aperture settings and exposure times to see what works best for you, but that's the fun part. Choosing a clear night from a good site and away from any pollution will also give you better results.
There are plenty of astrophotography books available which go into a lot of detail on all the aspects of digital cameras and the results you can expect from them, and if you are in any doubt it's worth investing in one to ensure you get all your questions answered.
A couple of points to take into account is that if you intend to take deep space images there is a limitation on exposure length and electronic noise can sometimes be a problem.
If deep space is really your thing than a dedicated CCD would be the better option.