HD PENTAX-DA 20-40mmF2.8-4ED Limited DC WR

The first zoom lens of the Limited Lens series, designed for use with PENTAX K-mount lens-interchangeable digital cameras




RICOH IMAGING COMPANY, LTD. is pleased to announce the launch of the HD PENTAX-DA 20-40mmF2.8-4ED Limited DC WR interchangeable lens, designed for use with PENTAX K-mount lens-interchangeable digital cameras. Developed as the first zoom lens of the acclaimed Limited Lens series, this zoom lens features a lens-installed AF driving motor and a dependable weather-resistant construction.

This model is the first zoom lens of the high-grade Limited Lens series, which is renowned for its exceptional visual description, distinctive appearance and meticulous finish in every detail. It features a two-times zoom range covering focal lengths from moderate wide angle to standard, and a large maximum aperture of F2.8 at its wide-angle end. In addition to the state-of-the-art HD coating and completely round-shaped diaphragm, it also comes equipped with a weather-resistant construction for the first time in the Limited Lens series, and a smooth, quiet AF system driven by a lens-installed AF motor, to capture beautiful, high-quality images, even under demanding weather and environmental conditions.

Main Features

1. The first two-times zoom lens of the Limited Lens series

With its two-times zoom coverage from 20mm to 40mm, this lens offers a focal-length coverage from 30.5mm to 61.5mm (in the 35mm format) when mounted on a PENTAX K-series lens-interchangeable digital cameras body. It provides the most frequently used focal lengths required for many popular applications, such as scenic photography, snapshots and portraiture, making it the ideal choice as an all-purpose, everyday lens.

2. Acclaimed Limited Lens-series quality for superb visual description and premium appearance

Inheriting the design concept of the Limited Lens series, this lens is designed with an optical construction that faithfully reproduces the feeling of depth while minimizing astigmatism over the entire zoom range. It allows the photographer to optimize the subject's visual description, by making its appearance softer at larger apertures and sharper at smaller apertures. Its lens barrel, hood and cap are made of a high-grade aluminum material, and hand-machined for perfect proportions and beautiful texture. Positioned in the mid-section of the lens barrel, the zoom ring features a series of knurled grooves to facilitate zooming operation.

3. State-of-the-art optical technology

The lens has been treated with the PENTAX-developed HD coating*, a high-grade, multi-layer coating that reduces reflectance in the visible light spectrum to less than 50 percent of that of conventional multi-layer coatings. This allows the user to capture crisp, high-contrast images free of flare and ghost images, even under such adverse lighting conditions as backlight. It also incorporates an ED (Extra-low Dispersion) glass and a super-low-dispersion glass element in its optics to deliver clear, high-resolution images with edge-to-edge sharpness, while effectively compensating for chromatic aberrations over the entire zoom range.

* HD stands for High Resolution.

4. The first weather-resistant lens in the Limited Lens series

This lens is the first Limited Lens-series model to feature a weather-resistant construction, with seven special seals to prevent the intrusion of water and moisture into the lens interior. By mounting it on a PENTAX weather-resistant digital SLR camera body, the user is assured of greater durability and reliability when shooting in the rain or mist, as well as at locations subject to spray or splashes.

5. Other features

  1. ・Smooth, quiet AF operation using a lens-installed AF driving motor.
  2. ・Round-shaped diaphragm to produce a natural, beautiful bokeh (blur) effect, while minimizing the streaking effect of point light sources.
  3. ・The lens features the 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.
  4. ・SP (Super Protect) coating to keep the front surface free of dust and stains.
  5. ・ A choice of black or silver color.


Focal Length 20-40mm
(in 35mm format equivalent) 30.5-61.5mm
Maximum Aperture F2.8-4
Minimum Aperture F22-32
Lens Construction 9elements in 8groups
Angle of View 70-39°
Lens Mount KAF3
Minimum Focusing Distance 0.28m (0.9 ft.)
Maximum Magnification 0.20×
Filter Diameter 55mm
Diaphragm Control Fully automatic
Number of Diaphragm Blades 9
Rounded aperture (20mm: F2.8-4 40mm: F4-5.6)
Aperture Ring N/A
Tripod Compatibility N/A
Lens Hood MH-RA55
Lens Cap O-LW65A
Lens Case P70-150
Maximum Diameter x Length Approx.71mm x 68.5mm (2.8 inch x 2.7 inch)
Weight Approx.283g /10.0 oz (with hood Approx.291g /10.3 oz)
Bundle Case, Hood, Lens cap, Mount cap
Others HD Coating
SP (Super Protect) Coating
Quick-shift Focus System

Note: Designs and specifications are subject to change without notice.

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