This is a wide-angle zoom lens with exceptional mobility. Two aspherical lenses are used for effectively correcting distortion, field curvature, coma aberration, and other adverse effects for providing delineation performance. High-refraction low-dispersion glass is used for obtaining clear, high-detailed image quality.

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PENTAX's exclusive 3-group floating zoom technology reduces the field curvature over the entire zoom range. A ghostless coating is used to provide sharp, clear images with high contrast even under backlit conditions. The minimum shooting distance is 0.4m over the entire zoom range, and the maximum shooting magnification is 0.21X (at 55mm), which is performance rivaling single focal point lenses. A large flower-shaped hood with PL filter operation window is also included.