|HD||The HD multi-layer coating is applied to the surface of lens elements. It boosts light transmission, ensures sharp and high contrast images, minimizes ghosting and flares. The HD coating reduces reflections 50% more efficiently in comparison with traditional smc coating throughout the visible spectrum and has exceptional hardness, which ensures its increased durability.|
|DA||Autofocus lens for Pentax APS-C digital SLR cameras. Has no aperture control ring and only supports electronic aperture control from the camera.|
|ED||The lens incorporates low dispersion elements to minimize chromatic aberrations and ensure excellent sharpness and contrast even at maximum aperture.|
|WR||Water Resistant lens.|
|DC||The lens is equipped with micromotor to provide moderately fast and quiet autofocus.|
|LIMITED||High-quality lens with compact and robust build. Meets the highest standards and provides excellent performance and flawless image quality unachievable with traditional optical technologies.|
|Diagonal angle of view:||70.5°-38.9° (Pentax APS-C)
|Lens construction:||9 elements in 8 groups, including:|
|1 Super ED|
|Number of blades:||9|
|Closest focusing distance:||28 cm|
|Magnification ratio:||1:5 @ 40 mm at the closest focusing distance|
|Type of autofocus motor:||Micromotor|
|Full-Time Manual Focus:||Yes|
|Maximum diameter x Length:||Ø71 x 68.5 mm|
|Weather sealing:||Water-resistant barrel|
|Fluorine coating:||Front element|
|Filter size:||55 mm|
Design and Features
The first zoom lens in the high-performance Pentax Limited lens series, providing attractive appearance and a meticulously detailed finish. This lens is also the first Limited Lens-series model to feature a weather-resistant construction.
The build quality is excellent. The lens barrel is of moderate weight, water-resistant, made of metal. The lens mount is metallic. The zoom ring is not very broad, but located in the mid-section of the barrel and features a series of grooves to provide a good grip and prevent slippage of fingers. The physical length of the lens increases only by 6-7mm with zooming. Like all Pentax DA Limited series lenses, this model is equipped with recessed distance scale and a depth of field scale
The lens has rather narrow focal range. Formally it is the disadvantage, however in practice it contributes to a good compensation of optical aberrations and equally high image quality at the entire focal range.
The lens uses front filters with standard size of 55 mm which are easy to find. They are also inexpensive.
A fluorine coating has been applied to the outer surface of the front lens element to repel water or oil drops for easier cleaning of the lens surface.
The lens is equipped with micromotor, the autofocus is low noisy and moderately fast. The lens features Quick-Shift Focus System: after autofocus is achieved, the focusing ring can be turned to adjust the focus manually. This feature eliminates the need for changing the focus mode to MF.
The focusing ring rotates during autofocus which looks pretty anachronistic by today's standards. It is strongly recommended not to touch the ring or manually stop its movement because it might result in damage to the lens and/or camera.
Being a technical masterpiece, this Limited lens is not only capable of producing excellent photos, but also gives aesthetic pleasure to its owner.
|Sensor size:||23.7×15.7 mm|
|Distortion at 20 mm:||-2.86 %|
|Distortion at 40 mm:||-0.47 %|
|Vignetting at 20 mm F/2.8:||-1.02 EV|
|Vignetting at 40 mm F/4:||-0.96 EV|
Alternatives (AF, 17-45 mm)
|Sigma 20-40mm F/2.8 EX DG Aspherical||2001||⊗|