Picture angle and focal length – Nikon D200 User Manual
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Technical Not
es—
Optional A
cc
essories
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 lens
Type D lens
Type G lenses are not equipped with a lens aperture ring. Unlike other CPU lens-
es, 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
The diagonal picture angle of the D200 is less than that of a 35-mm cam era.
When cal cu lat ing the focal length of the lenses for the D200 in 35-mm format,
mul ti ply the focal length of the lens by about 1.5:
Option
Approximate focal length (mm) in 35-mm format (modifi ed for picture angle)
35-mm camera
17
20
24
28
35
50
60
85
D200
25.5
30
36
42
52.5
75
90
127.5
35-mm camera
105
135
180
200
300
400
500
600
D200
157.5
202.5
270
300
450
600
750
900
The size of the area exposed by a 35-mm
camera is 36 × 24 mm. The size of the
area exposed by the D200, in contrast,
is 23.6 ×15.8 mm, meaning that the diago-
nal picture angle of a 35-mm camera is ap-
proximately 1.5 times that of the D200.
Cal cu lat ing Picture Angle
Picture size (D200)
Picture size (35-mm format)
Lens
(23.6 mm × 15.8 mm)
Picture diagonal
(36 mm × 24 mm)
Picture angle (35-mm format)
Picture angle (D200)