I may have been doing this wrong, as from what I got from how to take the exposures, obviously its over and under exposed, but I understood it as you take a whole range of shots, like say -2, -1, 0, +1, +2. So you would have 5 shots that photomatix or PS would put together, but is it not like that?
Should I just be taking ONE picture at -2, and then another at +2?