Pentax smc DA 50mm f/1.8 lens review: accessible price and excellent aberration control

Introduction

Measuring just 38.5mm in length and weighing 122g, this tiny featherweight prime boasts a fast f/1.8 maximum aperture. As a moderate telephoto the 35mm full-frame equivalent to a 75mm when mounted on an APS-C body, this lens is particularly suited to indoor portraits and candid ‘street’ photography.

Achieving a DxOMark score of 19 points, however the Pentax smc DA 50mm f/1.8 lens isn’t quite up to the overall capabilities of rivals, at least when paired with the 16-Mpix Pentax K5. Although this lens can be commended for its negligible distortion, excellent control of vignetting and extremely low levels of chromatic aberration, the acutance and resolution, cumulatively expressed in our Sharpness score is, to some extent, disappointing. Sharpness across the field wide open is also a little on the low side, though that’s not always a bad thing for a portrait lens.

The lens scores well when compared with others in the range, including the firm’s highly regarded Limited and DA Star models. Indeed it comes second in our DxOMark rankings in the range, just one point beneath the best performing model, the Pentax smc DA Star 55mm f/1.4 SDM. With a sticker price of just $249, this lens is an intriguing proposition for Pentax users.

Pentax smc DA Star 55mm F1.4 SDM	640	20
Pentax smc DA 50mm f1.8	249	19
Pentax smc DA 35mm F2.4 AL	220	18
Pentax smc DA 70mm F2.4 Limited	545	18
Pentax smc PENTAX D FA 50mm F2.8 Macro	444	17
Pentax smc D FA MACRO 100mm F2.8 WR	589	17
Pentax smc DA 35mm F2.8 Macro Limited	700	17
Pentax smc FA 50mm F1.4	450	17
Pentax smc DA 40mm f2.8 XS	250	16
Pentax smc DA 40mm F2.8 Limited	360	15
Pentax smc DA Star 200mm F2.8 ED (IF) SDM	1200	15
Pentax smc DA Star 300mm F4 ED (IF) SDM	1400	15
Pentax smc DA 21mm F3.2 AL Limited	650	14
Pentax smc PENTAX DA 14mm F2.8	575	13
Pentax smc DA 15mm F4 ED AL Limited	510	13