ISO 517-2008 摄影技术.照相机镜头光圈及其相关特性.名称和测量法

标准号：ISO 517-2008
中文标准名称：摄影技术.照相机镜头光圈及其相关特性.名称和测量法
英文标准名称：Photography - Apertures and related properties pertaining to photographic lenses - Designations and measurements
标准类型：N46
发布日期：1999/12/31 12:00:00
实施日期：1999/12/31 12:00:00
中国标准分类号：N46
国际标准分类号：37.040.10
适用范围：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.