This large-aperture standard zoom lens is the latest model of the new-generation Star series, which is designed to provide the best possible image quality and accommodate the super-high-performance cameras of the future. Its newly designed optics assures greatly improved contrast and sharpness compared to previous models while compensating various aberrations to a minimum and delivering sharp, clear images not only in the middle of the image field but at 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 effectively minimizes chromatic aberration over the entire zoom range.

Advanced Features

The newly designed zoom optics features a lighter, more compact focus-lens group. This focus-lens group is driven by an advanced PLM (Pulse Motor), which assures smooth, high-speed autofocus operation with minimized noise. A redesigned focus mechanism provides a minimum focusing distance of just 0.3 meters and a maximum magnification of 0.24 times, making this a handy lens for capturing all types of subjects — from everyday snapshots to close-ups and landscapes.

Performance

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 f/2.8, 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.

Exceptional Resolving Power

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. 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.

PLM (Pulse Motor)

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 the focus-ring operation.

Electromagnetic Diaphragm Mechanism

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.

Dustproof, Weather-resistant Construction

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.