Canon 9520B002 EF 11-24mm f/4L USM Wide Angle Lens

The Canon EF 11-24mm f/4L USM stands alone as the widest rectilinear zoom lens available for full-frame DSLRs, offering a remarkable 126° diagonal angle of view at 11mm. Its optical formula consists of 16 elements in 11 groups, including one Super UD element and one UD element that work together to minimize chromatic aberration. Four aspherical elements correct distortion and astigmatism from center to edge, delivering impressively rectilinear results even at the widest setting. Canon's proprietary Subwavelength Coating (SWC) and Air Sphere Coating (ASC) are applied to reduce flare and ghosting, which is critical for an ultra-wide lens frequently exposed to oblique light sources. A 9-blade circular aperture contributes to smooth background rendering when shooting at closer distances.

Autofocus is driven by a ring-type Ultrasonic Motor (USM) paired with a high-speed CPU and optimized algorithms, delivering fast and virtually silent focusing. The rear-focus design keeps the front element stationary during focusing and allows full-time manual focus override without switching out of AF mode. Built to Canon's L-series standards, the lens body is sealed against dust and moisture, and fluorine coatings on the front and rear elements resist smudges and water droplets. At 108mm in diameter and 132mm in length, the lens is solidly built but compact relative to its capabilities, though its 1180g weight is worth considering for extended handheld shooting.