Af-Assist Illumination; Calculating Picture Angle - Nikon D5000 User Manual

_I_ AF-Assist Illumination
AF-assist illumination is not available with the following lenses:
• AF-S NIKKOR 14-24mm f/2.8G ED • AF-S VR 200mm f/2G ED
• AF-S VR 70-200mm f/2.8G ED • AF-S VR 200-400mm f/4G ED
• AF-S 80-200mm f/2.8D ED
At ranges under 1 m (3 ft. 3 in.), the following lenses may block the AF-assist illuminator and
interfere with autofocus when lighting is poor:
• AF-S 17-35mm f/2.8D ED •
• AF-S DX 17-55mm f/2.8G ED •
• AF-S DX NIKKOR 18-105mml/3.5-5.6G EDVR •
• AF-S DX VR 18-200 mm f/3.5-5.6G ED •
[] Calculating Picture Angle
The size of the area exposed by a 35 mm camera is 36 x 24 mm. The size of the area exposed
by the D5000, in contrast, is 23.6 x 15.8 mm, meaning that the picture angle of a 35mm
camera is approximately 1.5 times that of the D5000. The approximate focal length of lenses
for the D5000 in 35 mm format can be calculated by multiplying the focal length of the lens
by a bout 1.5.
Lens
AF-S NIKKOR 24-70mm f/2.8G ED
AF-S VR 24-120mm f/3.5-5.6G ED
AF-S 28-70mm f/2.8D ED
AF-S VR Micro 105mm f/2.8G ED
Picture size (35ram format)
f
f
Picture diagonal
_\ Picture size (D5000)
(23.6x 15.8mm)
Picture angle (35mm format)
Picture angle (D5000)
197