Pentax 100mm f/2.8 SMC D-FA WR

The Pentax 100mm f/2.8 SMC D-FA WR Macro is designed for D-SLRs such as the Pentax K-r, K-5 and K-7 and features a maximum aperture of f/2.8 and a minimum aperture of f/32. With Pentax’s lineup of D-SLRs featuring APS-C sized sensors and a 1.5x crop factor, the 35mm film equivalent focal length sits at 150mm.

Pentax 100mm f/2.8 SMC D-FA WR

Pentax 100mm f/2.8 SMC D-FA WR

Comprising an internal arrangement of 9 glass elements in 8 groups, it feels reasonable in the hand despite being light at 345g. Capable of focusing within 30.3cm of any subject, the front element accepts 49mm filters and features a multi-layer coating, designed to minimise surface reflection, reduce ultraviolet rays and deliver high-contrast images. The focusing system isn’t the internal type, so when it focuses down to life-size at a 1:1 reproduction ratio the front element extends 46mm from the end of the lens, though it doesn’t rotate.

Being a weather resistant (WR) lens, the focus ring offers a good level of grip and the focus distance indicator offers a ratio guide between 1:25 and 1:1. With no motor to reduce the noise of AF operation, it whirrs and groans while in use and we noticed it had a tendency to hunt on far-off subjects before eventually locking focus.

At £480, it’s a fairly expensive option considering it doesn’t share all the features of some of its closest rivals. 

Specification

This review was first published in the October 2011 issue of Digital Photo - download back issues here.