Assertion: lens's length | /r/HasProperty | equal
Facets:
value: approximately
type: DEGREE
Source sentences:
text: A lens is considered to be a "normal lens", in terms of its angle of view on a camera, when its focal length is approximately equal to the diagonal dimension of the film format or image sensor format.
text: A high-quality prime lens whose focal length is about equal to the diameter of the film frame or sensor may be constructed from as few as four separate lens elements, often as pairs on either side of the aperture diaphragm.