Nikon introduces fast, wide-angle to medium telephoto AF-S zoom lens optimized for edge-to-edge sharpness on both the Nikon FX (23.9 x 36mm) and DX-format image sensors. Enhanced optical formulas, engineered to produce exceptional sharpness, contrast and color, render outstanding image integrity. Two ED (Extra-low Dispersion) elements and PGM aspherical lenses control chromatic aberrations while enhancing sharpness and contrast, even at the widest aperture settings.Exclusive Nano Crystal Coat further reduces ghosting and flare for even greater image clarity. Nikon's Silent Wave Motor (SWM) enables ultra high-speed autofocusing with exceptional accuracy and powerful, super-quiet operation. Internal Focus (IF) provides fast and quiet auto focusing without changing the length of the lens, retaining subject-working distance through the focus range. M/A Focus Mode switch enables quick response to changing situations between Auto and Manual focus operation