I got interested in this type of photograpphy last summer and bought a book on it. It was very technical but I got the jist of the procedure. My camera (Canon xti) bracketts three exposures, one being under exposed (you pick the setting) one correctly exposed, and one over exposed. This will give you a good range of detail in the dark areas as well as the light areas. The final image will manifest the detail from the combination of these three images, making it very much more like the eye sees it. It is a wonderful expansion of my photo techniques and you can see some samples in my portfolio. I will post more on HDR photography in future blogs.