This standard zoom lens has been developed as the latest model of the new-generation Star (★) series, designed to provide improved image quality and high-speed, high-precision autofocus operation to accommodate the super-high-performance digital cameras of the future. By incorporating the latest optical design technologies, the optics has been completely redesigned to assure high-resolution, high-contrast images even at open aperture. Compared with the existing smc PENTAX-DA★ 16-50mm F2.8ED AL[IF]SDM launched in July of 2007, this lens delivers greatly improved imaging performance. It also incorporates a PLM (Pulse Motor) for the first time in a large-aperture lens to assure high-speed, low-noise autofocus operation. It is even fine-tuned for greater operability in manual-focus operation. This new zoom lens allows users to fully enjoy the process of photography according to their own preferences.

A new-generation Star-series lens, assuring high-contrast, high-resolution imaging even at image edges, and delivering clear, crisp images with minimal aberrations
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.

New-generation, high-performance Star-series lens to deliver ideal image quality
Anticipating the further advancement of SLR camera bodies in the future, PENTAX has designed this lens to deliver extra-clear, high-contrast images with edge-to-edge sharpness by compensating various aberrations to a minimum, while greatly enhancing resolving power — two factors absolutely essential in the next-generation Star series. It provides exceptionally high imaging performance even at open aperture, a beautiful bokeh (defocus) effect and outstanding image rendition at close ranges — all reasons why it produces high-quality, well-defined images. It also boasts an extra-large F1.4 maximum aperture, useful with many different subjects in a range of applications, including portraiture with an effectively defocused background, handheld shooting of indoor scenes and scenic photography. It helps the camera to produce a bright, clear viewfinder image that will inspire the photographer’s creativity and imagination.

Exceptional resolving power assured by uncompromising optical design
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.

High-performance PLM for quiet, high-speed autofocus operation
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 using AF.S mode for viewfinder shooting of still images, at a distance of 0.3 meters to infinity.

Electromagnetic diaphragm mechanism for flawless, high-precision exposure control during video recording
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.
^{*Compatible KAF4-mount models are: PENTAX K-3 Mark III, PENTAX K-3 II, PENTAX K-3, PENTAX KP, PENTAX K-70, PENTAX K-50, PENETAX K-S2, PENTAX K-S1, PENTAX K-1 Mark II, and PENTAX K-1. We advise that users upgrade the camera’s firmware to the latest version to properly use electromagnetic diaphragm control.
**Models compatible with video recording in AF.C mode are: PENTAX K-3 Mark III, PENTAX K-70 and PENTAX KP. We advise that users upgrade the camera’s firmware to the latest version for optimum video recording performance.}

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.

Other Features

• Round-shaped diaphragm to produce a natural, beautiful bokeh (defocus) effect, while minimizing the streaking effect of point light sources.
• SP (Super Protect) coating to keep the front surface free of dust and spots.
• Quick-Shift Focus System for instant switching from autofocus to manual-focus operation, by holding the shutter-release button halfway down and turning the focus ring after the subject is captured in focus by the camera’s AF system.