f-number

f-num ber |ˈɛf ˌnəmbər | ▶noun Photography the ratio of the focal length of a camera lens to the diameter of the aperture being used for a particular shot (e.g., f8, indicating that the focal length is eight times the diameter ). ORIGIN early 20th cent.: from f (denoting the focal length ) and number .

f-number

f-number ▶noun Photography the ratio of the focal length of a camera lens to the diameter of the aperture being used for a particular shot (e.g. f8, indicating that the focal length is eight times the diameter ). ORIGIN early 20th cent.: from f (denoting the focal length ) and number .