The ratio of image size to sensor size. 1:1 means a lens can take a photo of a subject the same size as its sensor. 1:3 means the smallest object a lens can photograph is 3 times the size of the camera sensor. Reproduction ration = 1 / maximum_magnification. See the lens tables for lists of maximum magnifications for various lenses.underwatterphotography
Specifically the size of the image recorded on film divided by the actual size of the subject.
Term used in macrophotographyto indicate the magnification of a subject; specifically the size of the imag recordedon film divided by the actual size of the subject; for example, if the image on filmis the same size as the subject, the reproduction ratio is written as 1:1 or 1X