The Sigma 17-40mm f/1.8 Art: A Big Upgrade or Just Another Fast Zoom?

Sigma’s 17-40mm f/1.8 DC Art is trying to replace a lens many people have built entire systems around, the 18-35mm f/1.8 Art. If you rely on one fast zoom on APS-C for video, interviews, or hybrid work, this lens is definitely worth a look.

Coming to you from Thomas Fransson, this thoughtful video walks through how the new Sigma 17-40mm f/1.8 DC Art lens compares to the older Art zoom and Sigma’s smaller 18-50mm f/2.8. Fransson shows that the 17-40mm has a very modern, punchy look with strong microcontrast, while the 18-35mm stays a bit smoother and more forgiving, especially on faces and talking heads. You see how both lenses are sharp, but the newer lens adds more “pop” that can make backgrounds feel slightly busier. That difference in rendering becomes obvious in his sample clips from the FX30, particularly when he moves between portrait distances and wider environmental shots. If you care as much about how skin and texture feel on screen as you do about sharpness charts, this comparison is worth paying attention to.

Fransson also digs into how Sigma got an f/1.8 zoom this compact and what tradeoffs come with that. The 17-40mm leans harder on in-camera corrections, while the Sigma 18-35mm f/1.8 DC HSM Art does more of the heavy lifting optically. When he puts both lenses on a full frame body, the 17-40mm shows stronger distortion and a smaller image circle, where the 18-35mm covers more of the frame and keeps straight lines looking a bit cleaner. That matters if you ever shoot real estate, interiors, or anything with a lot of vertical and horizontal lines that need to stay straight. 

Key Specs

• Focal length: 17 to 40mm (35mm equivalent: 25.5 to 60mm on APS-C)

• Maximum aperture: f/1.8

• Minimum aperture: f/16

• Mount options: Sony E, Fujifilm X, Leica L, Canon RF

• Format coverage: APS-C

• Minimum focus distance: 11 in / 28 cm

• Maximum magnification: 0.21x (1:4.8)

• Optical design: 17 elements in 11 groups

• Aperture: 11 rounded blades

• Image stabilization: none

• Filter size: 67 mm front thread

• Dimensions: 2.9 x 4.6 in / 72.9 x 115.9 mm

• Weight: 19.8 oz / 560 g

Beyond distortion and coverage, the video highlights how much imaging corrections matter once you move into video. Still images can use baked-in profiles in camera and raw profiles in Lightroom or Capture One, but video corrections can stretch pixels in ways that make stabilization glitchy and lines bend in odd ways. Fransson talks about why you might prefer the more “honest” distortion of the 18-35mm for motion work, where less in-camera correction tends to mean cleaner footage and fewer warping artifacts when you stabilize in post. He also walks through how barrel distortion at the wide end shifts toward pincushion as you zoom, so you understand what you are seeing as you scrub through the comparisons. That part alone helps you judge your own lenses more critically.

Build and handling are another area where the 17-40mm feels like a new generation. You get an aperture ring, function buttons, iris lock, and proper weather-sealing in a smaller, lighter package that takes 67mm filters instead of the 72mm filters used on the 18-35mm. Autofocus on the new lens is quiet and quick, which matters if you rely on internal mics or like to let the camera handle focus while you move around. At the same time, Fransson shows that an 18-35mm paired with a Sigma MC-11 adapter can still be very reliable on Sony, so you are not forced to upgrade purely for focus speed. He also brings the Sigma 18-50mm f/2.8 DC DN Contemporary into the mix as a lighter travel option if you want something smaller while keeping the older Art zoom for more serious work. The video goes deeper into real-world autofocus behavior, breathing, flare, and bokeh that you will probably want to see in motion rather than just read about. Check out the video above for the full rundown from Fransson.