It seems that the rush Nikon have been through to bring enough D100s to the market has put a dent in their quality control. When I first got my D100 I was amazed with its performance and could not understand why some people were complaining about underexposure and sharpness issues. If anything I had to dial minus compensation to avoid blown ups. Granted, the pictures using the Normal or Auto tone compensation are a little in the low contrast side, but they printed beautifuly. Well my camera had a cluster of hot pixels at relatively low shutter speeds before the noise reduction could kick in so I got it exchanged. The next one was always underexposing by at least half a stop. Indoor pictures under tungsteen lights were the worse, not to mention cloudy days. Pictures were dark, dull and lacking contrast. And as the sharpening on digital camera is based on contrast they looked rather unsharp. After postprocessing they're great but I decided to take it back to Nikon Canada in Toronto. They calibrated the CCD and the exposure meter. Lord bless them! Now the pictures I get are great right out of the camera are up to Nikon standards and with my tone compensation curve to perk up the contrast a bit they look just ready. I'm writting this in a hope to help out those having problems with the camera. I urge you to make a trip to your Nikon service center and have your camera calibrated if the underexposure problem is severe.