Canon EF 17-40mm f/4L USM Ultra-Wide Zoom Lens Technical Specs

A new and 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.

Estimated Retail Price
$839.99
Focal Length & Maximum Aperture
17 - 40mm; 1:4
Lens Construction
12 elements in 9 groups
Diagonal Angle of View
104° - 57° 30'
Focus Adjustment
Inner focusing system with USM
Closest Focusing Distance
0.28m / 0.9 ft.
Zoom System
Rotating type
Filter Size
77mm
Max. Diameter x Length, Weight
3.3" x 3.8", 1.1 lb. / 83.5 x 96.8mm, 500g



Canon EF 17-40mm f/4L USM Ultra Wide Angle Zoom Lens for Canon SLR Cameras


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