Canon EF 17-40mm f/4L USM Wide Angle Lens
The technical details behind this lens
Canon EF 17-40mm f/4L USM Wide Angle Lens offers durable construction and sophisticated optical design. It features a Super Spectra coating, it has been applied to suppress flare and ghosting for improved contrast in difficult lighting environments. One Super UD element is offered, along with three aspherical elements, which help to reduce both chromatic and spherical aberrations in order to realize high sharpness, clarity, and colour accuracy. The constant f/4 maximum aperture maintains consistent illumination throughout the zoom range. This lens is weather-sealed for use in harsh environmental conditions. A ring-type Ultrasonic Motor (USM), along with an internal focusing system, is employed to provide fast, precise, and quiet autofocus performance as well as full-time manual focus override. The 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. Overall, this incredible lens provides every great feature you need to make a difference.
- Aperture Range: f/4 to f/22
- Three Aspherical Element
- EF-Mount Lens/Full-Frame Format
- Rounded seven-blade diaphragm
Top three Reasons we think you will love this lens
- Features One Super Ultra-Low Dispersion Element
- Great Optical Performance
- Remarkable Construction
Our expert's opinion
You will love the sophisticated optical design of Canon EF 17-40mm f/4L USM Wide Angle Lens. One Super Ultra-Low Dispersion glass element noticeably reduces colour fringing and chromatic aberrations for high clarity and colour fidelity. For improved sharpness and accurate rendering, the three aspherical elements minimize spherical aberrations and distortions.