ISO 517:2008

Photography — Apertures and related properties pertaining to photographic lenses — Designations and measurements ISO 517:2008

General information

90.93 Standard confirmed   Dec 1, 2021

ISO

ISO/TC 172/SC 1 Fundamental standards

International Standard

37.040.10   Photographic equipment. Projectors

Scope

ISO 517:2008 pertains to apertures and related properties of photographic lenses affecting the illuminance at the centre of the image.
ISO 517:2008 specifies aperture markings for all types of lenses used in still cameras, and gives tolerances for the stop numbers. It also defines aperture stop, entrance pupil, focal length, relative aperture and stop numbers, and gives methods for their measurement or determination.
ISO 517:2008 applies only to lenses focused on objects at infinity; that is, at least 50 times the focal length of the lens.

Life cycle

PREVIOUSLY

WITHDRAWN
ISO 517:1996

WITHDRAWN
ISO 517:1996/Cor 1:2006

NOW

PUBLISHED
ISO 517:2008
90.93 Standard confirmed
Dec 1, 2021