Designed for use with PENTAX K-mount digital SLR cameras, this interchangeable zoom lens provides a high zoom ratio of approximately 5.3 times to cover focal lengths from 16mm ultra-wide-angle to 85mm telephoto (for focal lengths equivalent to 24.5mm to 130mm in the 35mm format).

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Developed in response to enthusiastic requests from advanced photographers, this interchangeable zoom lens not only provides the high 5.3-times zoom ratio, but it also features: the PENTAX-exclusive HD coating to deliver sharp, clear images even under demanding lighting conditions such as backlight; an ED (Extra-low Dispersion) optical element to effectively compensate for chromatic aberrations; and aspherical optical elements to minimize color bleeding. Its weather-resistant body makes it extremely dependable and durable under demanding outdoor conditions.