Sigma’s New 17-40mm f/1.8 Is a Game-Changing APS-C Zoom Lens

The Sigma 17-40mm f/1.8 DC Art lens is the first zoom of its kind, combining a wide focal range with an unusually fast aperture for APS-C and Super 35 cameras. Here's a look at what you can expect.

Coming to you from Josh Sattin, this detailed video breaks down the Sigma 17-40mm f/1.8 DC Art lens and shows it paired with Canon’s C70. The autofocus performance is demonstrated right away, and it keeps up with face and eye detection without issue. Image quality is sharp, contrast is pleasing, and flare is well controlled. Sattin notes the bokeh looks smooth, and chromatic aberrations don’t really show up in real-world shooting. Focus breathing is also kept under control, which is important if you shoot video.

The build quality is consistent with what you’d expect from the Art line: solid construction, a smooth zoom and focus ring, and an aperture control that you may or may not use. There’s no optical stabilization in the lens, so you’ll need to rely on in-body stabilization if your camera has it or stabilize in post. It’s a fully electronic focus-by-wire design, but with Canon cameras, you can set the ring to respond linearly to make manual focusing more predictable. Sattin points out the lens includes two programmable buttons and a weather-sealing gasket, which adds some useful flexibility for different setups.

Key Specs

• Focal Length: 17 to 40mm (35mm Equivalent: 25.5 to 60mm)

• Aperture: Maximum f/1.8, Minimum f/16

• Lens Mounts: Canon RF, Leica L, Sony E, Fujifilm X

• Format: APS-C

• Minimum Focus Distance: 11" / 28 cm

• Magnification: 1:4.8 Macro Reproduction Ratio, 0.21x Magnification

• Optical Design: 17 Elements in 11 Groups

• Aperture Blades: 11, Rounded

• Focus Type: Autofocus

• Image Stabilization: None

• Filter Size: 67 mm

• Dimensions: ø 72.9 x L 115.9 mm

• Weight: 535 g

Of course, the 17-40mm f/1.8 DC is being compared heavily to the older Sigma 18-35mm f/1.8. The new lens is lighter, slimmer, and has silent autofocus compared to the noisy focusing motor in the 18-35mm. You also get a slightly wider and longer range, which makes it more versatile for both video and stills. On Canon RF cameras, it will automatically crop, but cinema cameras give you the option of forcing full frame with heavy vignetting, which Sattin does not recommend.

Price-wise, the 17-40mm f/1.8 sits at $919, higher than the long-popular 18-35mm, which sells new for $800 and is easy to find used for around $500. Sigma’s smaller 18-50mm f/2.8 Contemporary is another alternative at $659, but it’s slower and not part of the Art line. The unique thing about the 17-40mm f/1.8 is that it could realistically replace a few primes while giving you the convenience of a zoom, which makes the cost easier to justify if you need that flexibility. Check out the video above for the full rundown from Sattin.