I should also note that it's easy to go overboard with HDR. First, not all scenes/images are amenable to HDR. (Some examples on the Photomatix site are a bit too much for me.) Second, one can play around with the parameters in Photomatix to come up with a really fake-looking image--e.g., lots of detail, but very flat.Third, it takes time--how much will depend, in part, upon your computer's speed. (Try not to run any other applications at the same time.) Fourth, the "improvement" you get (e.g., more detail in highlights and shadows) may not be worth the effort. I've done something like 150 HDR images but only a few are worth showing. (The images of the snowy street were not intended for showing to anyone, just for practice.)