diagonal than the focal length of the lens, the result is a narrow angle of
view. if the same lens is used with a larger negative, the angle of view is
The larger the negative to be covered by a lens of a given focal
length, the greater the angle of view.
(2) If the focal length is equal to the diagonal of the negative, the
angle of view decreases as the subject distance is shortened.
(3) Since manufacturers usually produce lenses for specific negative
sizes, they also prepare tables giving angles of view of commonly used lenses.
Some manufacturers also list angle of view for vertical and horizontal
measurements of film. For example, the readings for a 5-inch focal length lens
are diagonal 65, horizontal 53, and vertical 44.
(4) Figure 2-17 illustrates the angle of view for wide-angle, normal, and
long focal length lenses.
Angle of view for various focal length lenses.