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Pentax SMC DA* 55mm f/1.4 SDM Review


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  • Excellent ergonomics


  • Fringing in MTF images

Key Specifications

  • Review Price: £450

This is an expensive lens that looks classy and well-made. It is probably the ideal size for a standard lens, being neither so compact as to be difficult to use nor so large as to be unwieldy. Sadly, its performance does not fully match its exterior appeal.

The length of the lens barrel is split almost in half by the manual focus ring, which resides to the fore. Behind it there is a two-position AF/MF slider switch and a depth-of-field window that has markers for f/8 and f/22. Automatic focusing is brisk and allows manual intervention if required; switching to MF keeps the same feel but simply removes the powered option.

Being a DA design, the lens can only be used on Pentax digital bodies (FA lenses are designed for film bodies and DFA lenses suit both types of image capture). The ‘star’ specification denotes a premium level of build quality with an SDM (Supersonic Direct-drive Motor) AF system. Pentax describes the lens as the digital reincarnation of its classic 55mm FA* standard lens and highlights the addition of the latest anti-reflection coatings for increased light transmission. All of this helps to explain its £500 list price and even on-the-street it is unlikely to be found for less than £400.

Ergonomically the lens is a delight to use but technical testing revealed some disappointing fringing at wide apertures, accompanied by some rather low MTF results. From f/2.8 onwards things are much better and the lens performs satisfactorily in the majority of picture-taking situations. The quietness of the lens is particularly noteworthy.

Pentax SMC DA* 55mm f/1.4 SDM mtf data

Sample images


It seems like a shame that Pentax’s 55mm fast prime does not have full-frame coverage, but given that there is currently no full-frame Pentax body (other than older film cameras) this may not be such an important gripe. In isolation this would be a good lens once it has been stopped-down slightly, but amid a field of fast primes its slight weaknesses limit its overall score.

Trusted Score

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Score in detail

  • Value 9
  • Design 10
  • Image Quality 9
  • Features 9

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