Search query: aspherical lens canon

Product: Canon EF 17-40mm f/4L USM Ultra Wide Angle Zoom Lens for SLR Cameras
Brand: Canon
Color: Black
Relevance: Exact
17 40 millimeter ultra wide angle zoom lens with f/4 maximum aperture for Canon SLR Cameras. Diagonal angle of view 104° 57° 30'
3 aspherical lens elements and super UD glass element create superior optics in all conditions, Closest focusing distance: 0.9 feet
Powerful ring type ultrasonic monitor (USM) produces fast and silent autofocusing, Focuses as close as 11 inches, supports screw in 77 millimeter filters or up to 3 gel filters. Rounded seven-blade diaphragm contributes to a pleasing out of focus quality that benefits the use of shallow depth of field and selective focus techniques
Suitable for Wedding/Nature Photography, Weather resistant construction, Water and Dust Resistant, measures 3.3 inches in diameter, 1 year warranty
Purchase this product between May 1, 2016 and July 30, 2016 and get 13 months of free damage protection from Canon. The product must be registered within 30 days of the purchase date to be eligible

Product: Canon EF 20mm f/2.8 USM Wide-Angle Fixed Lens
Brand: Canon
Color: Black
Relevance: Substitute
Focal length and maximum aperture: 20mm 1:2.8
Lens construction: 11 elements in 9 groups
Diagonal angle of view: 94 Degree
Rear focusing system with USM focus adjustment
Closest focusing distance: 0.20m/0.66 ft.