Canon EF-S 10-22mm f/3.5-4.5 USM - £660
Canon's 10-22mm lens has a lot going for it. It's reasonably compact and lightweight, yet build quality feels solid and robust. The overall lens length stays fixed throughout the entire zoom range - a trick matched only by the Tokina 12-24mm f/4 AT-X 124 AF PRO DX II in this group. Zoom range is generous, equivalent to 16-35mm on Canon's APS-C bodies.
Luxuries include top-spec, ring-type ultrasonic autofocus, which comes with full-time manual override. Canon's Super Spectre coatings are used to reduce ghosting and flare, but uniquely in the group, the lens is supplied without a lens hood. The petal-shaped EW-83E hood has to be bought separately, and will set you back a further £30.
The USM autofocus proved practically silent, extremely fast and highly accurate in our tests, with nice smoothness in the focus and zoom rings. Sharpness was pretty good around the centre of the zoom range, but disappointing at each end. We needed to stop down to f/8 to get good results, but even then, sharpness at the widest 10mm focal length was poorest in the group. At f/16 it's still the lowest in the group, but it is more consistent across the focal range.
At the widest aperture, vignetting was also noticeable throughout the zoom range. At least peripheral illumination correction is available in-camera with most of Canon's current DSLRs. On the plus side, distortions are well-contained and chromatic aberrations are minimal.
Resolution sharpness test
Sharpness is consistent through the focal range, but lower overall than on other lenses. Peak performance is at the mid-focal length of 17mm.
At the centre point at all focal lengths fringing is minimal, but at 17mm and 22mm there are signs of blue fringing towards the edge.
The Canon lens has the least barrel distortion on test at the widest focal length. At 17mm and 22mm this changes to mild pinch distortion.
Image test verdict
While not an outstanding performer, the Canon lens does well. It produces good, consistent results across all our tests.