This affordable L-series ultra-wide-angle zoom lens that's ideal for both film and digital SLRs. Superior optics are assured by the use of three aspherical lens elements, in addition to a Super UD (Ultra-low Dispersion) glass element. Optical coatings are optimized for use with digital cameras. This lens focuses as close as 11 inches (0.28m), and offers both Canon's full-time manual focus and a powerful ring-type USM for fast and silent AF. It has a constant f/4 maximum aperture, and offers the choice of screw-in 77mm filters or a holder in the rear of the lens for up to three gel filters. Finally, it offers weather-resistant construction similar to other high-end L-series lenses.

• Three Aspheric Lenses
• 1 Super Ultra-low Dispersion glass element
• Inner/Real Focusing
• Full-Time Manual Focusing
• Circular Aperture

• EF 17-40mm f/4.0L USM Zoom Lens
• Lens Case LP1319
• Lens Hood EW-83E

• 93° - 49°20', 70°30' - 34°, 104° - 57°30'

• 12 / 9

• 7

• f/22

• 0.28m

• 0.24x (at 35mm)

• USM

• 77mm

• 3.3 x 3.8"

• 1.1 lbs