Decisive moment

The fraction of a second during which all of the elements of a photograph come together at the same time. Cartier-Bresson is credited with coining the term "decisive moment." He was the one who defined photography as "the simultaneous recognition, in a fraction of a second, of the significance of an event as well as of a precise organization of forms which give that event its proper expression." The term "decisive moment" has become synonymous with photography.
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