Reproduction ratio

The reproduction ratio of a lens relates to the size a subject is reproduced on the image sensor. ‘True’ macro lenses have at least 1:1 reproduction ratio, meaning a subject 2cm in length takes up 2cm on the image sensor. Some lenses that are listed as ‘macro’ actually exhibit smaller ratios than this, such as 1:2 (where a 2cm subject covers just 1cm on the image sensor) and that means you capture less detail. Conversely, higher magnification ratios, such as 2:1 mean a 2cm subject covers 4cm on the image sensor, providing larger-thanlife, near-microscopic levels of detail.