A Nikon Extra-Low Dispersion (ED) glass element delivers superior optical performance. ED glass minimizes chromatic aberrations, contributing to superb contrast and resolution performance. Internal Focus (IF) provides fast and quiet auto focusing without changing the length of the lens, retaining subject-working distance through the focus range. Versatile, High-power 7.5x Zoom-Nikkor lens (Approximates the picture angle performance of a 28-200mm lens on 35mm SLR).