Due to optical design and differences in construction, the area visible will differ even on binoculars with the same magnification. The area visible is called the ‘field of view’ and there are three expressions used in binoculars: real field of view, apparent field of view, and 1000 m field of view. In general, the wider the field of view, the easier it is to find objects, making binoculars more comfortable to use. In ISO standards and the new JIS standards for telescopes, an apparent field of view of 60 or more is called a wide field of view type, which is one of the criterias to choose binoculars.
|Real field of view
|1000 m field of view
|Apparent field of view
|The area that can be seen without moving the binoculars.
|The area at 1,000 m ahead that can be seen without moving the binoculars.
|The field of view visible through binoculars that appears at the same size as when looking with the naked eye.