Picture angle and focal length – Nikon D2Xs User Manual
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Technical Notes—Optional Accessories
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.”
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
The diagonal picture angle of the D2Xs is less than that of a 35-mm cam-
era. When cal cu lat ing the focal length of the lenses for the D2Xs in 35-mm
format, mul ti ply the focal length of the lens by about 1.5 (high-speed crop
mode off) or 2 (high-speed crop mode on):
CPU lens
Type G lens
Type D lens
Cal cu lat ing Picture Angle
The size of the area exposed by a 35-mm cam-
era is 36 × 24 mm. The size of the area exposed
by the D2Xs, in contrast, is 23.7 × 15.7 mm
(high-speed crop off) or 17.7 × 11.7 mm (high-
speed crop on). As a result, the picture angle
of photographs taken with the D2Xs 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.
Picture size
(D2Xs; high-speed crop off)
Picture size (35-mm format)
Lens
(23.7 mm
× 15.7 mm)
Picture size
(D2Xs; high-speed crop on)
(17.7 mm
× 11.7 mm)
Picture diagonal
(36 mm
× 24 mm)
Picture angle (35-mm format)
Picture angle
(D2Xs; high-speed crop off)
Picture angle
(D2Xs; high-speed crop on)
Picture angle
Approximate focal length (mm) in 35-mm format
(modifi ed for picture angle)
35-mm fi lm camera
20
24
30
36
135
202.5
270
300
450
600
750
170
360
400
600
800
1000 1200
210
900
157.5
180
200
300
400
500
600
105
42
52.5
75
90
40
48
56
70
100
120
170
34
127.5
25.5
28
35
50
60
85
17
Hi-speed crop: Off
35-mm fi lm camera
Hi-speed crop: On
D2Xs
Hi-speed crop: On
Hi-speed crop: Off
D2Xs