This model comes from Pentax's KB range, and the DA mark denotes its digital dedication...
The lens has a metal outer barrel with a plastic inner barrel, which extracts as the zoom is moved towards the wideangle end. There’s a wide grooved zoom ring, while the manual focus ring is much narrower at the edge of the metal outer barrel. The focus scale is engraved on this barrel in front of the manual focus ring. Despite being one of the smallest and lightest of the lenses in this category, it feels pretty solid, though it lacks the professional feel of Canon and Nikon counterparts. With no high-tech drive motors, the AF is much noisier than others and while it’s slower it’s not problematically so even for fast-moving subjects – thanks mainly to the AF module built into the camera body.
In terms of sharpness the lens proves itself a contender by providing high resolution over 1000lwph. It also maintains this throughout the aperture and focal range. Optically this is as close to perfect consistency as we’d like to see, but with the wider angle comes increased fringing, with a rise of 3-3.5 pixels from centre to corner. This is a prime example of the difficulties still to overcome in providing wideangle optics for digital sensors, especially if you need to maintain a certain price point.