Angle of View Figure
WIDE-ANGLE, "NORMAL," AND TELEPHOTO LENSES. Nearly all modem photographic lenses are more complicated than the simple lenses shown in Figure 2-8. Most are composed of sets of elements, such as those which are schematized at the top of this Figure. The 28 mm, 50 mm and 135 mm lenses are common wide-angle, "normal," and "telephoto" lenses in 35 mm photography, whether motion picture or still. Each of the three lenses diagrammed in the middle of the Figure is seeing the same arrangement of four columns from the same distance and perspective. The frames at the bottom are exact visualizations of the various images of the scene each lens produces. The wide-angle lens image appears to be taken from a greater distance; the telephoto image is greatly magnified. Notice the slight linear distortion in the wide-angle image and the flat" quality of the telephoto image. In 35 mm photography, the 50 mm lens is considered "normal" because it best approximates the way the naked eye perceives a scene.