PENTAX smc D-FA 645 55mm F2.8 – Description

55State-of-the-art optics

Incorporating high-performance, hybrid aspherical optical element in its optics, this new standard lens offers exceptional image-resolving power with outstanding brightness levels even at the edges, while compensating various aberrations to a minimum. All lens characteristics are optimized for digital photography: for instance, flare and ghost images are minimized by applying exclusive lens coatings to optical elements and employing anti-reflection materials for the interior of the lens barrel. As the result, this lens can bring out the full potential of the PENTAX 645D or PENTAX 645Z medium-format digital SLR camera.


Versatile standard lens

When mounted on the PENTAX 645D or PENTAX 645Z camera body, this standard lens offers a focal length of 43.5mm (in the 35mm format), which produces an angle of view close to that of the human eye. As the result, it can be used for many different kinds of subjects and applications, including landscapes and portraits.


Dependable dustproof, weather-resistant construction

Using seven special seals, the lens’ dustproof, weather-resistant construction effectively prevents the intrusion of dust and water to the lens interior. By coupling this lens with the PENTAX 645D camera body, the user is assured of a durable, reliable digital SLR camera system that performs superbly in outdoor settings, even in rain or mist or at locations prone to water splashes or spray.
PENTAX plans to use the “AW” (All Weather) designation in the product name of all dustproof, weather-resistant medium-format interchangeable lenses to be marketed in the future.


Aero Bright coating to dramatically improve image description in backlight

The lens is treated with PENTAX-original Aero Bright coating, which delivers brilliant, high-quality images by preventing annoying flare and ghost images more effectively than ever before. Born as the fruit of PENTAX’s advanced nanotechnology, this exclusive coating effectively reduces lens reflectance and greatly increases light transmittance by forming a silica aerogel layer with uniform pores on the surface of optical element.


Smooth, quiet SDM autofocus mechanism

The SDM (Supersonic Direct-drive Motor) autofocus mechanism operates smoothly and quietly using the supersonic motor installed inside the lens barrel.


SP coating to block dust and dirt

The front surface of the lens is treated with PENTAX-original SP (Special Protect) coating, which applies an exclusive fluorine compound to the lens surface through a vapour deposition process. This SP coating not only effectively repels dust, water and grease, but also makes it easy to wipe off fingerprints and cosmetics.


Rounded diaphragm to produce a beautiful bokeh

This is the first PENTAX medium-format interchangeable lens to features a completely rounded diaphragm. It creates a natural, beautiful “bokeh” (out-of-focus rendition), while minimizing the streaking effect of point light sources.


Other features

  1. Image circle covering the image area of 645-format film SLR cameras
  2. Functional, simplified design, with no aperture ring
  3. Quick-Shift Focus system for instant switching to manual-focus operation, after the subject is captured in focus by the AF system
  4. PL filter window for easy installation of a polarizing filter without removing the lens hood
  5. PH-SA67 Square Plastic Hood (optional) for more effective prevention of flare and ghost images when mounted on the PENTAX 645D or PENTAX 645Z camera body

smc D-FA 645 55mm F2.8 – Specifications

Article Number
Article Number 26350
Technical Specifications
Focal Length 55mm
Equivalent to 35mm format Equivalent to 43.5mm in 35mm format with 645D body
Equivalent to 34mm in 35mm format with Film 645 body
Maximum aperture f/2.8
Minimum aperture f/22
Number of Diaphragm Blades 9
Fully Automatic diaphragm control
Angle of View 53° (with 645D body)
65° (with Film 645 body)
Construction 9 Elements in 7 groups
Focusing Range 0.5m to infinity (1.65 ft. to infinity)
Smallest object distance/magnification
Magnification Maximum 0.17x
Filter size 67mm
Mount 645 AF2
Weight 416g (14.7 oz.)
Dimensions (Length x Diameter) 81.3mm x 68.2mm (3.2 inch x 2.7 inch)
Kit Content Lens Hood PH-RBN 67mm
Lens case S100-120
Special metal front cover cap
Rear lens cap
Special Features Quick-Shift Focus System
Aero Bright Coating
SP (Super Protect) coating
Dust proof, Water resistant (AW)