Nikon AF-S DX 10-24mm f/3.5-4.5G ED - £670
There are many similarities between the Nikon and Canon lens tested, despite the Nikon's slightly bigger zoom range. Nikon's ring-type Silent Wave autofocus is fast, quiet and accurate, just like the Canon 10-22mm optic's USM system, and the layout of the focus distance scale, slim focus ring and big zoom ring is almost identical.
Weight-wise the Nikon lens falls in the middle of the group, but build quality is high. The zoom ring moves smoothly, with enough friction to feel positive without being stiff. The major difference is that the zoom rings work in opposite directions. With the Nikon, you twist the ring clockwise (viewed from the rear of the lens) to increase focal length. This is more common, being used by all the lenses tested apart from the Canon and Olympus.
There was only minor vignetting in our tests, even at the widest available apertures, which rise from f/3.5 to f/4.5 as you go through the zoom range. More remarkably, at f/3.5, f/8 and f/16, sharpness is the best in the group at the shortest focal length, although it's poor at longer focal lengths.
Distortions are more noticeable than with some lenses throughout the zoom range, but there's little colour fringing. All Nikon's current APS-C cameras feature automatic distortion and chromatic aberration correction. All in all, the Nikon is a star performer, especially at the extreme wide-angle end of the zoom range.
Resolution sharpness test
At f/16 centre sharpness is good throughout the focal range. Towards the edges, at all focal lengths, sharpness drops.
Signs of fringing at all focal lengths are minimal across the focal range. At 24mm there is a slight visible sign of red fringing towards the edge.
The Nikon produces the worst barrel distortion in the test, visible at 10mm. At other focal lengths there is mild pinch distortion.
Image test verdict
At the crucial widest focal length the Nikon centre sharpness is excellent, but the lens does suffer from heavy barrel distortion.