ACalculating Angle of View (Continued)
The DX (24×16) angle of view is about 1.5 times smaller than the
35 mm format angle of view, while the 1.2× (30×20) angle of view is about 1.2 times smaller and the 5 : 4 (30×24) angle of view is about
1.1times smaller. To calculate the focal length of lenses in 35 mm format when DX (24×16) is selected, multiply the focal length of the lens by about 1.5, by about 1.2 when 1.2× (30×20) is selected, or by about 1.1 when 5 : 4 (30×24) is selected (for example, the effective
focal length of a 50 mm lens in 35 mm format would be 75 mm when DX (24×16) is selected, 60 mm when 1.2× (30×20) is selected, or 55 mm when 5 : 4 (30×24) is selected).
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