Nikon 17-55mm f/2.8G AF-S IF-ED - £1065/$1425
A hefty lens with battleship build quality, this 17-55mm is the discerning professional's choice. Indeed, there's nothing amateurish about its price tag. Even so, the cheaper equivalent Sigma and Tamron lenses both feature optical stabilisation, which is lacking in the Nikon lens.
The 17-55mm's ring-type ultrasonic autofocus system is spectacularly fast and unerringly accurate. It's even faster than the similar system fitted to both the Nikon 16-85mm and Sigma 24-70mm lenses on test. There's plenty of travel in the focus ring, too, which aids precise manual focusing in MF mode and when overriding autofocus.
Overall image quality is excellent, but sharpness is no better than with the Nikon 16-85mm lens in the 17-55mm sector of its zoom range. Sure, the cheaper Nikon's sharpness drops off a little at 85mm, but the pro lens doesn't offer this focal length anyway.
Distortion is similar between the two lenses, and fringing is slightly better on the 16-85mm. The only real bonus of this lens is the larger maximum aperture, which is just over a stop faster.
Sharpness test
A good performer, but sharpness isn't better than it is in the 17-55mm portion of the Nikon 16-85mm lens' range.
Lab test at f/8
Sharpness at wide angle: 2345
Sharpness at mid range: 2421
Sharpness at telephoto: 2494
Fringing test
Chromatic aberration is among the highest on test at 17mm, even though it's reduced by current Nikon DSLRs.
Lab test at f/8
Fringing at wide angle: 1.25
Fringing at mid range: 0.36
Fringing at telephoto: 0.18
Distortion test
From barrel distortion to pin-cushion, performance is almost identical to Nikon's cheaper 16-85mm lens.
Lab test at f/8
Distortion at wide angle: -3.27
Distortion at mid range: 1.35
Distortion at telephoto: 1.14
Image quality verdict
There's no real increase in image quality compared with Nikon's 16-85mm, though the 17-55mm does have a faster maximum aperture.
