If, like me you’re not planning on following the full frame Canon EOS 5D or Canon EOS 1Ds route quite yet, but still want an extreme wide angle, then this is Canon’s answer. Although it’s significantly cheaper than the Nikon 12-24 DX, the lens feels well made and all controls operate smoothly. Fit and finish are in a different league from the cheap plastic of the Canon 18-55 EF-S. That’s only as you would expect with a £ 500 / $ 650 lens. In 35mm or full frame digital terms this lens is equivalent to a 16-35mm lens which is great - I’ve missed really wide lenses since I went digital. Incidentally Canon EF-S lenses can only be used on the Canon EOS 20D, 30D, 300D, 350D and the Digital Rebel and Rebel XT. They can not be used on any other Canon camera bodies.

Canon 18-55mm EF-S at 18mm

Canon 10-22mm EF-S at 10mm - Seriously wide.

Performance is better than I’d expect from such an extreme lens - no disastrous fall off in sharpness or illumination in the corners at full aperture. OK there is a little but not much. Stopped down to f 5.6 very fine detail is recorded everywhere except the extreme corners. Distortion, although present is also lower than expected and correction is readily available from both PTlens and DxO. So far I’m impressed with the Canon 10-22 EFS - My only complaint is that at this price level the hood shouldn’t be a £ 30 extra.

The second frame below was taken from the same spot but with the Canon 10-22 EF-S at 10mm - about 16mm in film or full frame terms. Changes in focal length of only a few millimeters make a much bigger difference with wide angle lenses than with telephotos where an 8mm difference would be barely noticeable.