Tamron SP AF 17-50mm f/2.8 XR Di II VC - £345
There's a lot to like about this lens. The fast f/2.8 maximum aperture is constant throughout the zoom range and it features Tamron's potent 4-stop optical stabiliser (Vibration Correction). This puts it in competition with Canon's EF-S 17-55mm f/2.8 lens but the Tamron is smaller, lighter and less than half the price.
Build quality feels reassuringly good and the lens bears Tamron's SP (Super Performance) stamp. One area that could be improved, however, is that autofocus is based on a humble micro- motor and is a little sluggish and noisy as a result.
It's certainly no match for the ring-type ultrasonic system fitted to Canon's 17-55mm, or the similar USD (UltraSonic Drive) featured in Tamron's more recent 70-300mm telephoto zoom lens.
We tested this lens a couple of years ago and weren't massively impressed with its image quality. But Tamron seems to have upped its game, as the sample we received this time was very sharp throughout the zoom range, even at f/2.8. Distortions and vignetting are well controlled, with colour fringing negligible.
At the price, the lens is a great option for anyone wanting a fast-aperture standard zoom without paying over the odds.