Greetings! I've been search for the past few hours on this subject through various sites and forums, and haven't found anything helpful. I'm a pseudo-newbie to SLRs, and I just got a Sigma 50mm f/2.8 macro lens for my Nikon D60, and I'm getting some pretty fantastic results, but I have to have the lighting perfect before I'm able to get a good shot. I tend to get a lot of bright "fog" in close-ups, or it's just way too dark. I have no idea what to do about the fog, though I'm pretty sure that decreasing the f-stop would help dark shots. Problem is, no matter what setting on the D60 I use, I cannot change the aperture to anything less than f4.2. I've seen the aperture drop to f2.8 two times, but I can never retain it. What am I missing? Any info on the fog or the aperture problem would be immensely appreciated!