Canon EF 17-40mm f/4L USM Lens

Canon EF 17-40mm f/4L USM Lens
The Canon EF 17-40mm f/4L USM is a legendary ultra-wide zoom in the professional L-series lineup, prized for its excellent color rendition, sharp optics, and lightweight design. Perfect for landscapes, architecture, and interior photography, this lens offers a constant f/4 aperture throughout the zoom range. Built to withstand the rigors of professional use, it remains a favorite for photographers who need a durable, high-performance wide-angle solution that won’t weigh down their kit.

Professional L-Series Optics
Advanced Glass Elements: The optical design features one Super Ultra-Low Dispersion (UD) element and three aspherical elements. This combination effectively eliminates color fringing and distortions, delivering high-resolution images with superb edge-to-edge clarity.

Super Spectra Coating: Individual elements are treated with Canon’s proprietary coating to minimize ghosting and flare. This ensures your photos maintain high contrast and neutral color balance, even when shooting in harsh, direct light.

Constant f/4 Aperture: The maximum aperture remains consistent across the entire zoom range, providing predictable exposure and consistent illumination from 17mm to 40mm.

Versatile Range: While designed for full-frame sensors, it serves as a fantastic standard zoom on APS-C models, providing a 27.2-64mm equivalent focal length.

Precision Focus & Handling
Ring-Type USM Autofocus: Equipped with a powerful Ultrasonic Motor (USM), this lens delivers lightning-fast and near-silent autofocus. It also supports full-time manual focus override, allowing you to make fine adjustments without leaving AF mode.

Internal Focusing: The lens maintains its physical length during focusing, which is ideal for using circular polarizers and other position-sensitive filters.

Dual Filtering Options: In addition to the standard 77mm front filter thread, this lens features a rear gelatin filter holder, allowing you to use up to three cut gel filters for creative color or exposure control.

Built for the Elements
Weather-Sealed Construction: As a member of the elite L-series, this lens is built with a dust- and moisture-resistant design, allowing you to continue shooting in challenging weather and environmental conditions.

Lightweight Workhorse: Despite its rugged build, the 17-40mm is notably portable, making it an excellent choice for travel and hiking where every ounce matters.

7-Blade Diaphragm: Features a rounded diaphragm that produces smooth out-of-focus areas, enhancing your shots when using shallow depth-of-field techniques.

Included Accessories
Canon EW-83E Lens Hood: Engineered to block stray light and protect the large front element from accidental impact.

Technical Specifications
Focal Length: 17-40mm (27.2-64mm on APS-C)

Aperture Range: f/4 – f/22

Lens Mount: Canon EF

Filter Size: 77mm (Front) / Rear Gelatin Holder

Weight: Approx. 1.1 lbs (500 g)