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.

 ***  Filter Thread 58 mm ***

Comparable APS-C Focal Length: 82.5 mm

Focal Length  55 mm

Aperture Maximum: f/1.4

Minimum: f/22

Camera Mount Type Pentax K

Format Compatibility Pentax Digital (APS-C)

Angle of View 28.6°

Minimum Focus Distance 1.48' (45 cm)

Magnification 0.17x

Maximum Reproduction Ratio 1:5.7

Groups/Elements 8/9

Diaphragm Blades 9

Features

Image Stabilization No

Autofocus Yes

Tripod Collar No

Physical

Dimensions (DxL) Approx. 2.8 x 2.6" (7.11 x 6.60 cm)

Weight 13.23 oz (375 g)