From ultra-wide angle zoom on full-frame cameras or a standard zoom on DSLR's with APS-C sensors, on which this lens delivers 28-70mm equivalent.
Maintaining a f/4 maximum aperture means there is no need to vary shutter speed or ISO as you zoom.
Super Spectra coating on the elements ensures colour balance and minimises ghosting and flare to ensure you'll be proud of your image quality.
L-series is Canon's flagship professional lens range and EF 17-40mm f/4L USM delivers with its precision-designed EF optics.
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