For the more serious photographer or anyone looking to step up their game in the DSLR/photography world, the CanonEF 16-35mm f/4L IS USM lens is the perfect addition to your collection! This lens ranges from 16mm wide-angle to 35mm portrait-length telephoto; now that is what I call versatility! The lens is ultra-wide angle and water resistant! This lens also utilizes Canon's ring-type USM which gives you a silent but fast operation, giving you the best picture and video quality possible. SpecificationsFocal Length & Maximum Aperture 16-35mm 1:4:0.Lens Construction 16 elements in 12 groups. Diagonal Angle of View 10810' - 63.Focus Adjustment Inner focus system. Closest Focusing Distance 0.92 ft. / 0.28m.Filter Size 77mm diameter. Max. Diameter x Length, Weight 3.3 x 4.4 in, 21.7 oz. / 82.6 x 112.8mm, 615g.