Sigma 17-40mm F1.8 DC Art

Forget 'trinity' zooms, this new APS-C zoom is more than a full f/stop faster

- Matthew Richards

I haven't seen an APS-C lens quite like the Sigma 17-40mm F1.8 DC Art since 2013, when the company launched the 18-35mm F1.8 DC HSM Art for APS-C format Canon and Nikon DSLRs, as well as Sigma's SA mount cameras. The fast and constant f/1.8 aperture made the lens feel like a trilogy of 28mm, 35mm and 50mm prime lenses all rolled into one package. The new Sigma 17-40mm F1.8 DC Art has been redesigned for the mirrorless generation. It's smaller, lighter and has a bigger zoom range, equating to 25.5-60mm for Fujifilm X, Sony E and L-Mount APS-C cameras, and to 27.2-64mm for Canon EOS R system APS-C cameras.

Build and handling

I'm not the biggest fan of 'trinity' zooms as they're generally big, weighty, cumbersome and expensive. That said, there are plenty of lightweight, affordable alternatives from manufacturers and third-party lens makers, including the Sigma 28-70mm F2.8 DG DN Contemporary for full-frame mirrorless cameras. While the 17-40mm lens is designed for APS-C format instead of full-frame cameras, it's from Sigma's prestigious Art lineup, rather than the typically more compact and budget-friendly Contemporary stable.

One of the biggest attractions of a zoom lens is the versatility of adjusting your composition with the twist of a zoom ring. In this case, the ring works smoothly and precisely, taking you from a generous wide-angle coverage to a short telephoto length and everything between. The lens's zoom mechanism is internal, so the physical length doesn't change. That helps keep the weight centred if you're using a tripod and reduces the risk of moisture getting into the lens.

The lens is fitted with one of Sigma's HLA (High-response Linear Actuator) autofocus systems. Based on a linear stepping motor, it's designed to offer snappy and precise autofocus for stills, along with smooth and silent transitions for video.