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Pentax Telephoto 55mm f/1.4 DA* SDM Autofocus Lens for Digital SLR

Used Cat #3061252 • MFR #21790
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Pentax 21790 Overview

The Pentax 55mm f/1.4 DA* SDM Autofocus Lens is a compact and bright short-telephoto lens of the highest order, made exclusively for Pentax digital SLR cameras.  In a stocky housing ready for harsh conditions, you'll get a bright f/1.4 aperture-worlds away from the experience you're used to with more common zooms-that opens up new creative doors to you as a photographer.

This lens was born to shoot between f/1.4 and f/2.8, and comes with a 9-bladed aperture diaphragm which shows up as perfectly round when you stay between f/1.4-2.8.  Shoot dramatic portraits with bright point light sources behind the subject, and you'll be dazzled with lovely diffuse, circular out-of-focus highlights that make everybody look better.  Beyond portraits, this lens works well any time you would use a moderate telephoto focal length.

The focusing system of this lens is SDM only; there is no screw on the rear of the lens barrel to have the AF driven by a body-based motor.  This allows the lens to move incredibly quick, driven by an internal motor and with the Quick-Shift system providing manual override capacity to you any time you want it with no buttons to switch; but you'll need a Pentax body which allows SDM autofocus (all current Pentax bodies support SDM, but the *IST series does not).

Note:
Does NOT provide autofocus upon non-SDM-enabled Pentax cameras.
Brilliantly-sharp portrait lens which gathers plenty of light
Completely-rounded aperture diaphragm from f/1.4-2.8 for beautiful out-of-focus highlights
Speedy SDM autofocus motor provides fast, silent response with Quick-Shift full-time manual override
Pentax's unique SP water and dirt-repelling coating on both external surfaces
Pentax's "Aero Bright" internal lens yields high transmissivity and reduced flare
Dust and moisture-resistant housing
Essentially equivalent to an 82.5mm f/1.4 lens upon 35mm SLR cameras

Pentax 21790 Specs

Filter Size
58mm
f/Stop Range
1.4-22.0
Focal Length
55mm (35mm Equivalent: 82.5mm)
Minimum Focus Distance
1.5' (45cm)
Maximum Aperture
f/1.4
Minimum Aperture
f/22
Magnification
1:5.8
Angle of View
28.6°
Groups/Elements
8/9
Lens Mount
Pentax K
Length
2.6" (66mm)
Lens Format Coverage
APS-C
Maximum Diameter
2.8" (70mm)
Angle of View
28.6°
Weight
0.83 lb (375g)
Minimum Focus Distance
1.48' / 45 cm
Maximum Magnification
0.17x
Optical Design
9 Elements in 8 Groups
Diaphragm Blades
9
Focus Type
Autofocus
Image Stabilization
No
Filter Size
58 mm (Front)
Dimensions (ø x L)
2.8 x 2.6" / 7.11 x 6.6 cm
Weight
13.23 oz / 375 g

Pentax 21790 Reviews

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