The basis for a Nikon DSLR’s exposure meter is an RGB sensor that meters a wide area of the frame. When used with a G or D Nikkor CPU lens, the camera can set exposure based on the distribution of brightness, color, distance, and composition. Most people leave their cameras set to Matrix metering and enjoy excellent results. Others use the Center-weighted meter, or the Spot meter. Let's look more closely at each of the Nikon exposure meters.