A light metering mode. Once prevalent, now surpassed by matrix metering.
In center weighted metering
, the central area of the photogram is given more weight
. Formulas differ, but a typical one is that a circle with a 9 mm radius at the center of the photogram contributes with a weight of 70%, while the remaining area is 30%.
The logic behind this kind of metering is that (especially in amateur phtography) the subject is smack in the middle of the photogram, and the rest is background or simply junk.
As one progresses in photography, this becomes less true and one finds himself second guessing the meter and wishing for a true spot meter. On the other hand, center weighted metering is easier to second guess than matrix metering.
Contrast with spot metering, matrix metering. See also light metering for some general concepts.