Nature creates the most amazing colors! Digital photos of nature

Angle of view

This term is often confused with angle of field and field of view. The angle of view is the (diagonal) angle subtended by the scene captured in the photograph. This establishes the disc of best definition required for the lens. The angle of field is the angle subtended at the lens rear nodal point by the diagonal of the format itself. In a rectilinear image this is the same as the angle of view, but not for anamorphic images such as those produced by fisheye lenses. ‘Field of view’ simply describes the area covered in a scene. For example, although the angle of view of a fisheye lens is 180 degrees, its angle of field may be as low as 90 degrees. The field of view may be described as ‘horizon to horizon’. For a standard (prime) lens the angle of field is typically 50-55 degrees, the same as the angle of view, and the field of view is roughly the same as that of the eye in a normal viewing of a scene or a picture.

— Graham Saxby