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Technical Notes—Optional Accessories

Lenses

CPU lenses (particularly type G and D lenses) are recommended for use
with the D50 (note that IX Nikkor CPU lenses can not be used). CPU lenses
can be iden ti fi ed by the presence of CPU contacts. Type G lenses have no
aperture ring and are marked with a “G” on the lens barrel. Type D lenses
are indicated by a “D.”
CPU lens Type G lens Type D lens
Cal cu lat ing Picture Angle
The size of the area exposed by a 35-
mm camera is 36 × 24 mm. The size of
the area exposed by the D50, in con-
trast, is 23.7 ×15.6 mm, meaning that
the diagonal picture angle of a 35-mm
camera is approximately 1.5 times that
of the D50.
Picture size (D50)
Picture size (35-mm format)
Lens
(23.7 mm × 15.6 mm)
Picture diagonal
(36 mm × 24 mm)
Picture angle (35-mm format)
Picture angle (D50)