Perhaps the best advice that can be offered is to take the advice of those who have experience in the field of work on which you intend to focus. It is therefore important to consider carefully what you are trying to achieve. Once you have clear objectives, find and join a local club or society where you can meet a group of similar minded people. In most cases they will be only too pleased to talk about the instruments they use, and to demonstrate them to you. Although you may not get exactly the same advice from every individual, their collective experience should set you off on the right track.

If no suitable local club exists, do some research on the internet to see what equipment people use to achieve the type of results you wish to achieve. There are countless forums where questions can be asked, general advice sought, and discussions related to specific subjects can take place.

Begin the process of defining objectives by asking yourself simple questions such as how much money are you prepared to spend, how seriously you intend to pursue astrophotography, and what sort of pictures you want to take - lunar, planetary, deep-sky etc? The answers to these questions, even if not precise, will help to define the sort of camera that should suit your needs.