Nikon D2H User Manual page 242

CPU lenses can be iden ti fi ed by the presence of CPU contacts. Type G lenses
are marked with a "G" on the lens barrel, type D lenses with a "D."
CPU lens
Type G lenses are not equipped with a lens aperture ring. Unlike other CPU
lenses, there is no need to lock the aperture ring at the minimum aperture
setting (maximum f/-number) when using a type G lens.
Picture Angle and Focal Length
A 35-mm cam era has a di ag o nal pic ture angle ap prox i mate ly one-and-a-
half times that of the D2H. When cal cu lat ing the focal length of the lenses
for the D2H in 35-mm format, you will therefore need to mul ti ply the focal
length of the lens by 1.5, as shown in the following table:
Picture angle
35-mm fi lm camera
D2H
35-mm fi lm camera
D2H
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 D2H, in contrast,
is 23.3 ×15.5 mm. As a result, the picture
angle of photographs taken with the D2H
differs from the picture angle for 35-mm
cameras, even when the focal length of
the lens and the distance to the subject
are the same.
230
Type G lens
Approximate focal length (mm) in 35-mm format
(modifi ed for picture angle)
17 20 24
25.5 30 36
105 135 180
157.5 202.5 270
28 35
42 52.5
200 300
300 450
Lens
Picture angle (35-mm format)
Type D lens
50 60 85
75 90 127.5
400 500 600
600 750 900
Picture size (35-mm format)
(36 mm × 24 mm)
Picture diagonal
Picture size (D2H)
(23.3 mm × 15.5 mm)
Picture angle (D2H)