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HD PENTAX-D FA 28-105mmF3.5-5.6ED DC WR

  • Zoom
  • D FA
35mm Full Frame APS-C

A compact, lightweight standard zoom lens: high resolving power combined with outstanding maneuverability to be the perfect partner for PENTAX full-frame digital SLR cameras

Despite its compact, highly maneuverable body, this versatile zoom lens is designed to accommodate the image circle of a large full-frame image sensor, thanks to the adoption of state-of-the-art optics and high-performance optical elements. When mounted on PENTAX 35mm full-frame digital SLR cameras, it delivers high-resolution imaging power as an ideal everyday-use lens.

DC Weather-resistant Quick-Shift Focus Aspherical Lens (AL) SP Coating HD Coating Round Iris Diaphragm ED (Extra-low Dispersion) Glass


Hood : PH-RBC62 / Soft-Case : S80-120 Optional
JAN-Code / 4549212 294594

Sample Images

  • Aperture F8.0, Shutter speed 1/500sec, Focal length 37.0mm   Photo by KEI TANIGUCHI

  • Aperture F8.0, Shutter speed 1/320sec, Focal length 31.0mm, White balance Auto, ISO sensitivity 100, Finishing touch Vibrant

  • Aperture F20, Shutter speed 1/25sec, Focal length 28.0mm, White balance Auto, ISO sensitivity 100, Finishing touch Landscape
    *Publication Size : 2000×1335pixel

  • Aperture F5.0, Shutter speed 1/800sec, Focal length 28.0mm, White balance Auto, ISO sensitivity 100, Finishing touch Landscape
    *Publication Size : 2000×1335pixel

Main Features

Standard zoom lens covering most frequently used ranges
This standard zoom lens accommodates the image circle of a 35mm full-frame image sensor, and covers focal lengths between 28mm wide angle and 105mm medium telephoto. By incorporating the latest optics and a number of high-performance optical elements, it retains a sufficient brightness level even at edges of the image field, while effectively compensating for various aberrations. It delivers high-resolution images by optimizing the imaging power of PENTAX 35mm full-frame digital SLR cameras. Its compact, lightweight body and excellent cost performance make this lens a perfect regular lens.
Excellent image description, complementing the full-frame digital SLR camera performance
In its 15-element, 11-group optics, this zoom lens incorporates two high-precision aspherical optical elements, one ED (Extra-low Dispersion) glass optical element and one anomalous-dispersion glass optical element, to deliver bright, sharp images with minimal chromatic and spherical aberrations. Since its optics is designed to assure ample resolving power for the large, high-pixel image sensor, it produces well-defined, fine-detailed images.
HD Coating to improve image description
This lens is treated with the 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 that are free of flare and ghost images, even under demanding lighting conditions such as backlight.
* HD stands for High Definition.
Quick-Shift Focus System
This PENTAX-developed system allows for flawless, delay-free switching from autofocus to manual-focus operation, after the subject is captured in focus by the camera’s AF system.
Weather-resistant construction
This lens features a dependable weather-resistant construction with eight sealing parts to effectively prevent the intrusion of water into the lens interior. Paired with a weather-resistant PENTAX digital SLR camera body, it creates 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.
Other features
・SP (Super Protect) Coating applied to the front surface of the lens to effectively repel water and grease.
・Rounded diaphragm to produce a smooth, beautiful bokeh (defocus) effect, while minimizing the streaking effect of point light sources.
・Built-in DC motor to assure smooth, quiet, high-speed autofocus operation
【MTF Chart】
Geometric optics MTF (MTF calculated without referencing the effects of light diffraction phenomenon)



Wave optical MTF (MTF calculated referencing the effects of light diffraction phenomenon)



Spatial Frequencies S:Sagittal M:Meridional
10 lines/mm
30 lines/mm

Since it is impossible to avoid light diffraction phenomenon on the actual lens, wave optical MTF is more realistic.
However, geometric MTF is appropriate if you want to compare only the effects of geometric aberration correction on MTF.

What is the MTF chart?

Type Normal Zoom
Focal length 28-105mm
(when attached to PENTAX APS-C size DSLR cameras)
Maximum aperture F3.5-5.6
Minimum aperture F22-38
Angle of View 75-23.5°(when attached to PENTAX 35mm full-frame SLR cameras)
53-15.5°(when attached to PENTAX APS-C size DSLR cameras)
Lens construction 15 elements / 11 groups
No. of diaphragm blades 9
Closest focusing distance 0.5m (1.64 ft.)
Maximum reproduction ratio 0.22x
Filter size 62mm
Diameter x length approx. 73.0mm x 86.5mm (approx. 2.9in. x 3.4in.)
Weight approx. 440g / with hood approx. 463g(approx. 15.5oz./ with hood approx. 16.3oz.)

Compatible converters (Click here for details)


Phase-matching:△  Contrast-detection:△

*When mounted, this converter closes down the lens’s maximum aperture by one stop.

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