Nikon 1988 Instruction Manual - Page 9

Focusing on predetermined reproduction ratio until the image appears sharp on the focusing screen. • The tightening screw is indexed " 4 " for one-fourth. The reproduction ratio is, numerically, the relationship between the image size (to be recorded on the film) and the actual subject size. For example, if the image on the focusing screen is one-fifth the actual subject size, the reproduction ratio is 1:5. Two reproduction scales are inscribed in orange above the distance scale on the focusing ring. The inner scale, with figures from 1:10 to 2, represents reproduction ratios obtained when the lens is used alone. The outer scale figures (from 2 to 0.88) represent possible ratios when the lens and PN-11 ring are used together. Using either of these scales, you can photograph at a predetermined ratio without calculating distances. For example, to photograph at a reproduction ratio of 1:5, just turn the focusing ring until the number " 5 " is aligned with the distance index line; then aim at the subject and adjust your position (closer to, or farther away from the subject) Depth of field Depth of field refers to the zone of acceptable focus in front of and behind the area of sharpest focus in your shot. At high reproduction ratios, depth of field is extremely shallow; it's best, therefore, to preview before actual shooting. One way to do this is to press the depth-of-field button on your camera and the lens will close to the preselected aperture, showing you how much background and foreground is in focus. Another way is to read the color-coded indicators inscribed on the lens barrel. The pairs of colored lines on either side of the distance index line correspond to the f/numbers of the same color on the aperture scale. At close distances, however, so little is in focus that it may be more useful to check the depth-of-field tables on pages 32 and 33. 9