Description
Main Features
- Exceptional imaging power
- Consisting of 17 elements in 12 groups, the newly designed optics feature three ED (Extra-low Dispersion) optical elements, one anomalous-dispersion-glass aspherical optical element and three aspherical optical elements to accommodate super-high-resolution image sensors. By assuring sufficient light levels even at the edges of the image field and compensating various aberrations to a minimum, it provides a high MTF (Modulation Transfer Function) and delivers well-illustrated, fine-detailed images that are rich in contrast and resolution across the entire image field. When mounted on a current PENTAX K-series camera body, it uses only the central area of the image circle so that it delivers high-resolution images with uniform image description over the entire image field.
- Large-aperture standard zoom lens
- When mounted on a 35mm-format full-frame digital SLR camera body, this zoom lens offers a zoom ratio of approximately 2.9 times to cover the ultra-wide-angle to standard ranges (24mm to 70mm in focal length). It provides a maximum aperture of F2.8 over the entire zoom range to deliver brilliant images. It not only covers the focal-length range most frequently used for ordinary subjects, but also provides ultra-wide-angle coverage to produce distinctive visual expressions, such as exaggerated perspectives or extra-wide depths of field, making it very useful with subjects such as sweeping landscapes and shallow indoor scenes. When mounted on a current K-series digital SLR camera body, it provides focal lengths from 37mm to 107mm in the 35mm format to cover wide-angle to medium-telephoto ranges. Since its large maximum aperture not only creates an excellent bokeh (defocus) effect on the background for beautiful portraits, but also allows the photographer to handhold the camera for poorly illuminated subjects, such as sunsets and indoor scenes.
- Built-in SDM (Supersonic Direct-drive Motor)
- Thanks to the incorporation of a new-generation SDM (Supersonic Direct-drive Motor), this zoom lens assures quiet, high-speed autofocus operation, allowing the photographer to react swiftly to all types of subjects.
- Weather-resistant construction
- This lens features a dependable weather-resistant construction with special seals to effectively prevent the intrusion of water into the lens interior. By pairing it with a weather-resistant PENTAX digital SLR camera body, it assures a durable, dependable digital imaging system that performs superbly in demanding shooting settings ? even in rain or mist, or in locations prone to water splashing or spray.
- HD Coating to improve image description *2
- The lens is treated with high-grade, multi-layer HD Coating.* Compared with conventional multi-layer coatings, this PENTAX-original coating assures higher light transmittance and less reflection to deliver bright, high-contrast images free of flare and ghost images, even under demanding lighting conditions such as backlight. *2:HD stands for High Definition.
- Quick-Shift Focus system
- The lens comes equipped with the PENTAX-developed Quick-Shift Focus system, which allows the user to instantly switch to manual-focus operation after the subject is captured in focus by the camera’s AF system.
- Other features
- ・Rounded diaphragm to produce a smooth, beautiful bokeh (defocus) effect, while minimizing the streaking effect of point light sources.
・Zoom lock lever to prevent the accidental extension of the lens barrel when pointed downwards. - 【MTF Chart】
- Geometric optics MTF (MTF calculated without referencing the effects of light diffraction phenomenon)
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WIDE
TELE
- Wave optical MTF (MTF calculated referencing the effects of light diffraction phenomenon)
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WIDE
TELE
Spatial Frequencies S:Sagittal M:Meridional 10 lines/mm 30 lines/mm