Metering in Photography is the most common form of exposure measurement. It works on the principle of reflected light rays. If you are newbie about Photography, the articles on Digital Photography Basics and Digital single-lens reflex camera, these might be helpful for this topic on Metering.
What is Metering in Photography
The light intensity is on the entire surface under an assumption of a standardized gray tone would reflect exact 18 percent of incident light. In practice, this method results in its purest form, especially at high subject with high contrast often produces incorrect exposures, for example, bright sky in landscapes or portraits with a very bright or very dark environment, the real object is misperceived.

As the picture’s important motives are often at the center, in early stage, the center-weighted metering were used, Center Metering is at the more or less large area of the image section in the middle more than the image area between the center and the edges. This model is almost ideal to understand the basics of Metering in photography.
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Variants of Metering in Photography
Manufacturers of SLRs developed several refinements of the center-weighted metering.
These improved the reliability of average subjects and obtained a large part of the ordinary shooting. For unusual lighting conditionsfor the photographer, however, some experience with the idiosyncrasies of each camera model is necessary in order to take corrective action.
Center weighed metering : Metering method that is actually described above.
Spot Metering : Spot Meter is a dedicated light meter , which allows the photographer through a viewfinder to aim the light level to identify a very narrow range.
Average metering : This metering method gives no weight to any particular portion of the image.
Partial metering : Covers more area than Spot.
Multi-zone metering or Matrix Metering : In addition to the distribution of brightness depending on the camera, the color distribution and focal length of the lens are taken into account.
