Canon EF-S 10-22mm 1:3.5-4.5 USM

The Canon EF-S 10-22mm f/3.5-4.5 USM delivered a very sound performance with a combination of very decent build quality and very good if not impressive optical results. If anything vignetting at wide-open aperture could be better. The center performance is excellent throughout the range with generally good borders. The level of distortions is surprisingly low and CAs are quite well controlled.

Naturally it makes sense to compare the lens to a serious competitor like the Tokina AF 12-24mm f/4 AT-X Pro DX. All in all the resolution figures are very similar. The Canon has less CAs and a better contra light performance whereas the Tokina shows less vignetting. The build quality of the Tokina is also a little better (the Canon is more than "good enough" though) and finally the Tokina is substantially cheaper (420 EUR vs 670 EUR locally).

So which one to choose ? Well ... that's still up to you. :-)

The Canon EF-S 10-22mm f/3.5-4.5 USM is a very sound package thanks to a combination of very decent build quality and very good if not impressive optical results. The resolution is very high at 10mm and 14mm and still pretty good at 22mm. If anything vignetting at wide-open aperture could be better. The center performance is excellent throughout the range with generally good borders. The level of distortions is surprisingly low and CAs are quite well controlled (for an ultra-wide lens). Flare is also comparatively well-controlled. There's no such thing as a free lunch though - the EF-S 10-22mm f/3.5-4.5 USM sells for around 600€/US$ which is a whopping 50% higher than for third-party products such as the Tamron 10-24mm f/3.5-4.5 or the popular Tokina AF 12-24mm f/4 AT-X Pro DX.