This standard zoom lens is a member of the new-generation Star (★) series, designed to provide the greatly improved resolving power that will be demanded by tomorrow’s super-high-performance cameras. It delivers high-contrast, high-resolution images across the image field, even at open aperture, while producing a smooth, natural bokeh (defocus) effect to assure true-to-life image renditions. The incorporation of a high-performance PLM (Pulse Motor) provides much improved autofocus performance in both speed and precision. Despite the large maximum aperture of F2.8, this standard zoom lens assures outstanding maneuverability and portability — the most distinguished features of lenses exclusively designed for use with APS-C-format digital cameras — to accommodate all types of applications, from scenic and nature photography to snap-shooting and portraiture.

 

 

The 10-group, 16-element optical system (including four aspherical optical elements) assures superb resolving power and delivers super-clear, high-contrast images from the middle of the image field to the edges. By incorporating one ED (Extra-low Dispersion) glass optical element, one anomalous dispersion glass optical element and two ED (Extra-low Dispersion) aspherical glass optical elements, it reduces chromatic aberration to a minimum over the entire zoom range. The high-grade, multi-layer HD Coating,* which reduces the average reflectance in the visible ray spectrum to less than 50% that of conventional multi-layer coatings, effectively minimizes flare and ghost images even in demanding lighting conditions such as backlighting.

* HD stands for High Definition.

 

The focus-lens elements are directly driven by a PLM (Pulse Motor), providing much-improved focusing speed (approx. 2.2 times faster in the wide-angle range, or approx. 1.5 times faster in the telephoto range, compared to the smc PENTAX-DA★ 16-50mm F2.8ED AL[IF] SDM),* while effectively minimizing noise for quieter operation. Manual-focus operation of the power-assisted focus mechanism has also been upgraded to optimize the precision and response of detecting the focus ring. As the result, the focus-lens elements shift more efficiently and flawlessly in synchronization with focus-ring operation.

 

When mounted on a compatible KAF4-mount camera body, this zoom lens assures flawless, high-precision exposure control, not only in still-image shooting, but also in video recording. Even when there are considerable differences in brightness during video shooting, its electromagnetic diaphragm control mechanism allows the user to capture video clips using automatic exposure control. In combination with some compatible cameras,** the PLM (Pulse Motor) assures smooth focus tracking operation and flawless exposure control, while considerably reducing annoying noise generated by focus and diaphragm control operations during video recording. This means smooth, worry-free video shooting in locations prone to considerable brightness changes — such as a stage with rapidly changing lighting conditions, or a forest with filtering sunrays — or with active, fast-moving subjects such as athletes or animals.

 

This lens features the “All Weather (AW)” construction to prevent the intrusion of dust and water into the lens interior. Pair it with a PENTAX dustproof, weather-resistant digital SLR camera body for creative shooting in rain or mist, or other locations prone to water splashes.