17JpEnDeFrEsSeRuNlItCkChKrVariable maximum aperturesZooming the lens changes the maximum aperture byup to 1 1 / 3 stop.However, the camera will compensate for any changein aperture by adjusting the shutter speed so as tomaintain the correct exposure value.The built-in flash and vignettingVignetting is the darkening of the corners around theimage that occurs when the light emitted by the flashis obstructed by the lens hood 1, or lens barrel,depending on the focal length or shooting distance.• To prevent vignetting, do not use the lens hood 1.• The built-in flash cannot be used over distances ofless than 0.6 m (2.0 ft.).The built-in flash on the D100 and D70 is compatiblewith focal lengths of 20mm or greater.Vignetting occurs at a focal length of 18mm.Lens care• Be careful not to allow the CPU contacts 0 tobecome dirty or damaged.• Clean lens surfaces with a blower brush. To removedirt and smudges, use a soft, clean cotton cloth orlens tissue moistened with ethanol (alcohol) or lenscleaner. Wipe in a circular motion from the center tothe outer edge, taking care not to leave traces ortouch other parts of the lens.• Never use organic solvent such as thinner or benzeneto clean the lens.• NC filters are available to protect the front lenselement. The lens hood 1 also helps to protect thefront of the lens.• When storing the lens in its flexible lens pouch, attachboth the front and rear lens caps. The lens can also bestored with the lens hood 1 attached in the reverseposition.• When the lens is mounted on a camera, do not pickup or hold the camera and lens by the lens hood 1.• When the lens will not be used for an extended periodof time, store it in a cool, dry place to prevent mold andrust. Be sure to store the lens away from direct sunlightor chemicals such as camphor or naphthalene.• Do not get water on the lens or drop it in water as thiswill cause it to rust and malfunction.• Reinforced plastic is used for certain parts of the lens.To avoid damage, never leave the lens in anexcessively hot place.Digital-SLR cameras Supported focal length/shooting distanceD700/D300/D200/D100/D80No vignetting occurs at any focallengthD90/D70-series • 18mm/1.5 m (4.9 ft.) or greater• 24mm or longer/no restrictionsD50 • 18mm/1 m (3.3 ft.) or greater• 24mm or longer/no restrictionsD60/D40-series• 18mm/2.5 m (8.2 ft.) or greater• 24mm/1 m (3.3 ft.) or greater• 35mm or longer/no restrictions