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Pentax K5 II Features New Autofocus System

January 2 2013

by Philip Northeast

Pentax’s improved flagship compact DSLR, the new K5 II, sets the standard for performance for ASP-C sensor digital cameras, challenging full frame DSLRs with price tags more than twice its price.

Pentax say they have updated the K5 II’s autofocus system for better performance in low light, and improved the continuous focus system while tracking of moving subjects.  DxOMark sensor tests show the new K5 II’s ASP-C sensor has the same outstanding low light noise and dynamic range ability of the original K5.

Pentax K5 II

Pentax K5 IIs with the 18-55 WR (Weather Resistant ) Zoom

“The new K-5 II and K-5 IIs deliver an extensive range of photographic possibilities for the resolution-conscious photographer in all of us. As a successor to our popular K-5 camera, these new models offer upgraded features designed to produce superb image quality, including the new AF sensor which is especially useful for photographers working in low light conditions,” said John Carlson, Sr. Pentax’s Manager of Sales and Marketing.

According to Pentax the new SAFOX X Auto Focus system delivers a broad autofocusing EV (Exposure Value) range (-3 EV to +18 EV).  The AF system features an upgraded algorithm as well as the Select-Area Expansion feature, which automatically tracks the subject if it moves from a selected focus point, using information from adjacent focus points.

Pentax are also offering a K5 IIs model that comes without the anti-aliasing filter in front of the sensor. This filter is included in nearly all digital cameras to reduce the incidence of interference patterns, or moire, in digital photographs where there are patterns of fine lines.   The disadvantage of the aliasing filter is it limits the sharpness of the photos.  Considering the number of fantastic photos many photographers keep taking with DSLRs with the filter fitted it does not seem to be a severe problem. However, Pentax say for fine detailed studio and commercial work some photographers may appreciate the extra sharpness the K5 IIs offers without the filter.

Pentax have not changed the basic strengths of the original K5; it is still a rugged compact DSLR with exceptional low light capabilities and a wide dynamic range.

The Pentax K5 II has rugged metal construction with stainless steel and magnesium elements to keep all the optical elements in the camera precisely aligned.  The rough and tough theme continues with 77 special rubber seals in the body to keep out dust and moisture in the field. The go anywhere theme continues with a range of weather resistant  Pentax lenses so you can take the K5 II and use it in a variety of less than perfect conditions.

Compact DSLR

The K5 II is a compact DSLR making it an attractive proposition for photographers who do not want to lug around a full size DSLR such as the Nikon D4.  Analysis of the specifications reveals the Nikon is significantly larger and heavier than the Pentax. The Nikon is also around six times the price of the Pentax.


Width Height Depth Weight
Includes Battery and Memory card 
Pentax K5 II 131mm 97mm 73mm 740g
Nikon D4 160mm 156.5mm 90.5mm 1340g

In the DxOMark lab comparison the difference in performance is narrower than the price difference would suggest.  The K5 II even outperforms the Nikon in the dynamic range tests that suggest the suitability of a camera for Landscape photography


K5 II versus D4

DxOMark Pentax K5 II and Nikon D4 overall scores

The value of the big Nikon is indicated in the exceptional low light score confirming the D4 is a photojournalist’s tool, able to capture fast action in poor light.

DxOMark Lab Comparison

Our main three way comparison is looking at how the Pentax K5 II matches up to two Canon DSLRs.  The 7D is their top DSLR with an APS-C size digital sensor, while the 5D Mk III is a full frame DSLR priced for the professional market.

Price Comparison* 

Pentax K5 II (body only) $US1196.5 

Canon 7D (body only) $US1399

Canon 5D Mk III (body only) $US3299

*All prices from Adorama when the article was published.

DxOMark score summarry

DxOMark Pentax – Canon comparison score summary

The DxOMark sensor test score summary shows the Pentax K5 II performed significantly better than Canon’s best APS-C sensor camera, the 7D, in the areas of image noise and dynamic range.  To get a Canon that matches the Pentax, photographers need to dig deep into their wallets and go for the 5D Mk III. In this case the overall score is even, with the Canon producing less digital noise in photos for all ISO settings than the Pentax.

DxOMark Pentax - Canon image noise

DxOMark Pentax – Canon image noise test results

The Pentax K5 II turns the tables on both Canons in the dynamic range score.   The detailed DxOMark test results show this advantage is significant at low ISO settings.  Typically photographers use low ISO settings for situations where there is bright light, and consequentially areas of dark shadow.  Dynamic range indicates how the camera handles extremes of lighting conditions in the same scene. Once the camera’s dynamic range is exceeded details are lost in the highlights or the shadow areas.

dynamic range

DxOMark Pentax – Canon dynamic range comparison test



The digital sensor and the autofocus systems in the camera body are only part of the story. To go with the weather resistant camera body Pentax have a number of lenses that are sealed to resist moisture and dust. Naturally their premium DA* range of lenses are weather sealed, but Pentax are adding sealed lenses to their everyday range of lenses such as the workhorse 18-55mm zoom

Pentax also have a number of quality compact prime lenses that are easy to carry and still capable of producing superb results.

The K5 II has Pentax’s sensor shift Shake Reduction system to help reduce blurr from camera shake at slow shutter speeds, so photographers do not need special, and more expensive, IS or VR lenses.


The Pentax K5 II continues to offer class leading image performance in a compact and rugged package at a price offering great value for money.


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