Best lenses for the 24-MPix Pentax K-3: Recommended primes and zooms

By Kevin Carter - Monday January 06 2014

Lens Recommendations
Introduction | Lenses measured on Pentax K3: Database Overview | Best prime lenses for the Pentax K-3 | Best zoom lenses for the Pentax K-3

Although a full-frame lens and the equivalent to a 50mm on the Pentax-K-3, the Sigma 35mm f/1.4 DG HSM A is the best performing prime overall in our database (on the K-3). It’s a big heavy lens on the Pentax-K-3 but the build and image quality is very high. Peak sharpness is measured at 16P-Mpix, 3P-Mpix higher than the next measured model (the DA Limited 35mm f2.8 Macro –either the new HD model or earlier smc version).

Sigma 35mm F1.4 DG HSM A Pentax8992716
Pentax smc DA Star 55mm F1.4 SDM6402711
Pentax smc DA 50mm f1.82492512
Pentax smc DA 35mm F2.8 Macro Limited7002213
Pentax HD DA 35mm F2.8 Macro Limited7502213
Pentax smc DA 35mm F2.4 AL2202211
Pentax smc DA 70mm F2.4 Limited5452211
Pentax smc D FA MACRO 100mm F2.8 WR5892210
Pentax smc PENTAX D FA 50mm F2.8 Macro4442112
Pentax smc FA 50mm F1.44502111
Pentax smc DA 40mm f2.8 XS2502010
Pentax HD DA 40mm F2.8 Limited550199
Pentax HD DA 21mm F3.2 AL Limited7001811
Pentax smc DA 40mm F2.8 Limited360189
Pentax smc DA Star 300mm F4 ED (IF) SDM1400179
Pentax smc DA Star 200mm F2.8 ED (IF) SDM1200178
Pentax smc DA 21mm F3.2 AL Limited6501611
Pentax smc PENTAX DA 14mm F2.8575158
Pentax smc DA 15mm F4 ED AL Limited510149
Pentax HD DA 15mm F4 ED AL Limited700148

With the same DxOMark score of 27 points and technically occupying joint first place, albeit with a lower peak sharpness score is the Pentax smc DA* 55mm f1.4 SDM. As the equivalent to a 85mm on the K-3 it’s well corrected optically, and an excellent performer, though at $249 the more modestly priced APS-C only DA 50mm f1.8 isn’t quite as good a performer though with marginally higher peak sharpness it may appear to skew the ranking slightly when measured on the Pentax K-3.

Although we’ve not had the opportunity to analyze either the 16-Mpix K-5 II or the K-5 IIs (sans OLPF), we can compare the K-3 with the earlier K-5 (from 2010), which had related sensor. Although the overall pixel count increased 50% from 16.3-Mpix to 24.3-Mpix, the linear increase is much lower at around 22% - however, bearing in mind the Pentax K-3 has no OLPF increases in sharpness should be significant, especially with the right lenses.


Comparing the peak sharpness measurements of the DA * 55mm f1.4 on the K-3 and K-5 side-by-side shows an improvement at every aperture setting, including smaller apertures where diffraction plays a part.