F-number
id:
f-number-184-15624925
title:
F-number
text:
An f-number is a measure of the light-gathering ability of an optical system such as a camera lens. It is calculated by dividing the system's focal length by the diameter of the entrance pupil. The f-number is also known as the focal ratio, f-ratio, or f-stop, and it is key in determining the depth of field, diffraction, and exposure of a photograph. The f-number is dimensionless and is usually expressed using a lower-case hooked f with the format f/N, where N is the f-number. The f-number is al
brand slug:
wiki
category slug:
encyclopedia
description:
Measure of lens speed
original url:
https://en.wikipedia.org/wiki/F-number
date created:
2003-01-12T14:38:07Z
date modified:
2024-09-07T14:08:44Z
main entity:
{"identifier":"Q862169","url":"https://www.wikidata.org/entity/Q862169"}
image:
{"content_url":"https://upload.wikimedia.org/wikipedia/commons/8/87/Aperture_diagram.svg","width":512,"height":204}
fields total:
13
integrity:
16