To measure and compare the resolving power of the EF-S 10-22mm, we photographed the Enhanced Digital Camera Resolution Chart using it and a number of rival lenses mounted on a Canon EOS 400D. The 10-22mm was tested at a focal length of 22mm and the other three lenses at 35mm; all were set to f8 in Aperture Priority mode. The 400D was set to Large Fine JPEG mode and its Standard Picture Style.

The crops are taken from the original images, saved as High Quality JPEGs in Photoshop CS2 and presented here at 100%. Each number represents 100 lines per picture height (lpph), so a figure of 20 means a resolution of 2000 lpph.

In terms of horizontal resolution, the EF-S 10-22mm performs well, delivering 2100 lpph. This is slightly better than both the EF-S 17-85mm and EF-S 18-55mm lenses, although not quite as good as the EF-S 17-55mm.

In terms of vertical resolution, the EF-S 10-22mm again delivered 2100 lpph, this time matching the EF-S 17-85mm and EF-S 18-55mm lenses. Again though the EF-S 17-55mm takes a slight lead. So while the EF-S 17-55mm remains the resolution leader of the EF-S zooms, the EF-S 10-22mm certainly has nothing to be ashamed of. It matches or slightly out-performs all but the EF-S 17-55mm in this particular test. Note the EF-S 10-22mm was tested at 22mm, while the other three were tested at 35mm.