Metering Modes
Metering is a photography term which roughly means “light measurement”. In many “point and shoot” digital cameras, and in all DSLRs, several metering modes let you control the exposure of your photos. While digital camera manufacturers name them differently, there are three main metering modes found in modern digital cameras.
Matrix Metering (Evaluative, Multi-Zone, Multi-Segment)
This mode is used in most digital cameras as the default metering mode. The camera divides the whole picture into several zones and measures the light intensity in each of them in order to find the best exposure for the whole picture. This mode is best used when the subject takes up a large part of the frame and when shooting panoramas.
Center-Weighted Metering
This mode is also known as Center-Weighted Average Metering. When your digital camera is in this mode, it meters the entire frame, but gives greater weight to the center of the scene. Using this mode when your main subject is in the center of the frame emphasizes it, while keeping from isolating it from the surrounding areas.
Spot Metering
Spot, or Partial, metering mode instructs the digital camera to optimize the exposure by measuring the light intensity only at a given spot in the center of the frame. In some digital cameras, this spot can be moved along with the af frame, allowing the photographer to meter the shot in any area of the picture.