As Dennis wrote above, the most likely cause of the problem is you have Negitive Exposure Compensation dialed in. Press the Exposure Compensation button on the top of the camera and look at the top LCD. While holding the button down, rotate the command dial until 0.0 is indicated in the top LCD. You might want to make sure that you didn;t inadvertantly turn Bracketing On. Good Luck and Enjoy your Nikons!