Canon has made a bold statement with its latest L-series lens, but is the world’s widest-angle rectilinear zoom lens all it’s made out to be? Michael Topham puts the f/4L USM to the test
Canon EF 11-24mm f/4L USM – Introduction
When it comes to choosing a wideangle lens, photographers using a Canon full-frame DSLR have one of the best ranges available. For those working to a strict budget there’s the very respectable EF 17-40mm f/4 L USM, while for those who can justify the cost there’s the superb EF 16-35mm f/4L IS USM, which benefits from having a built-in optical image stabiliser – a feature Canon’s similarly excellent, but even more expensive EF 16-35mm f/2.8L II USM doesn’t have. If these zooms aren’t wide enough, there’s also the EF 8-15mm f/4L Fisheye USM and the EF 14mm f/2.8L II USM to consider, not forgetting Canon’s wideangle tilt-and-shift TS-E lenses, plus third-party options from the likes of Sigma, Tamron and Tokina.
Although it’s hard to fault this range of wideangle zooms available for full-frame landscape or architectural shooters, there has always been a demand for a zoom lens that covers a wider focal range than 16-35mm and delivers similar, if not better image-quality performance to Nikon’s highly respected AF-S Nikkor 14-24mm f/2.8G ED. It’s great to see Canon finally addressing the missing link in its L-series range, but has the EF 11-24mm f/4L USM been worth the wait?
Canon EF 11-24mm f/4L USM – Features
Unlike a fisheye lens that produces a distinctly curvilinear wideangle result, where straight lines often appear curved, the EF 11-24mm f/4L USM is a rectilinear lens yielding images in which straight features, such as the walls of buildings, appear straight as to the human eye. Such is the time and effort put in by Canon’s engineers to ensure that this lens displays minimal barrel or pincushion distortion, it has resulted in the widest angle of view ever to be achieved by a rectilinear full-frame DSLR lens. Put into perspective, the angle of view of the lens (126° 5’) is so wide – and so much wider than that offered by Canon’s 16-35mm zooms – that there was the odd occasion when my tripod legs would creep into shot when composing in the portrait format.
Turning our attention to the construction, the lens employs a 16-elements-in-11-groups arrangement, with four aspherical elements, one being the ground aspherical type to help tackle distortion. As to be expected from an L-series lens, ultra-low dispersion (UD) and super ultra-low dispersion elements also feature, as do three different types of lens coatings to guard against aberrations, ghosting and flare.
The USM abbreviation indicates that this lens uses Canon’s Ultra Sonic Motor technology to drive the autofocus system, and with full-time manual-focus override present, users can adjust the focus manually at any time without needing to flick the AF/MF switch to manual. With claims of a near-silent AF performance, the lens focuses with a low-frequency whirr that’s not picked up by the camera’s microphone, unless you record video in silence with no ambient sound.