Nikon 25414 D2Xs User's Manual - Page 260

CPU lenses can be identified by the presence of CPU contacts. Type G lenses are marked with a "G" on the lens barrel, type D lenses with a "D." Technical Notes-Optional Accessories CPU lens Type G lens Type D 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 The diagonal picture angle of the D2Xs is less than that of a 35-mm camera. When calculating the focal length of the lenses for the D2Xs in 35-mm format, multiply the focal length of the lens by about 1.5 (high-speed crop mode off) or 2 (high-speed crop mode on): Picture angle Approximate focal length (mm) in 35-mm format (modified for picture angle) 35-mm film camera 17 20 24 28 35 50 60 85 Hi-speed crop: Off 25.5 30 36 42 52.5 75 90 127.5 D2Xs Hi-speed crop: On 34 40 48 56 70 100 120 170 35-mm film camera 105 135 180 200 300 400 500 600 Hi-speed crop: Off 157.5 202.5 270 300 450 600 750 900 D2Xs Hi-speed crop: On 210 170 360 400 600 800 1000 1200 Calculating Picture Angle The size of the area exposed by a 35-mm camera is 36 × 24 mm. The size of the area exposed Lens by the D2Xs, in contrast, is 23.7 × 15.7 mm (high-speed crop off) or 17.7 × 11.7 mm (highspeed 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. 246 Picture size (35-mm format) (36 mm × 24 mm) Picture diagonal Picture size (D2Xs; high-speed crop off) (23.7 mm × 15.7 mm) Picture size (D2Xs; high-speed crop on) (17.7 mm × 11.7 mm) Picture angle (35-mm format) Picture angle (D2Xs; high-speed crop off) Picture angle (D2Xs; high-speed crop on)