Nikon D70S - Manual (Page 195)

185
Technical Notes—Optional Accessories
Picture angle
Approximate focal length (mm) in 35-mm format
(modifi ed for picture angle)
35-mm fi lm camera 20 24 28 35 50 60 85 17
D70S 30 36 42 52.5 75 90 127.5 25.5
35-mm fi lm camera 135 180 200 300 400 500 600 105
D70S 202.5 270 300 450 600 750 900 157.5
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 D70S, in contrast,
is 23.7 ×15.6 mm. As a result, the picture
angle of photographs taken with the
D70S 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 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 D70S. When cal cu lat ing the focal length of lenses for the
D70S 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 size (D70S)
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 (D70S)