Macro photography (or photomacrography or macrography, and sometimes macrophotography), is extreme close-up photography, usually of very small subjects, in which the size of the subject in the photograph is greater than life size (though macrophotography technically refers to the art of making very large photographs). By some definitions, a macro photograph is one in which the size of the subject on thenegative or image sensor is life size or greater. However in other uses it refers to a finished photograph of a subject at greater than life size.
The ratio of the subject size on the film plane (or sensor plane) to the actual subject size is known as the reproduction ratio. A macro lens is classically a lens capable of reproduction ratios greater than 1:1, although it often refers to any lens with a large reproduction ratio, despite rarely exceeding 1:1.
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