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Sigma 18-35mm F1.8 DC HSM

 & Jim Fisher Principal Writer, Cameras

Our team tests, rates, and reviews more than 1,500 products each year to help you make better buying decisions and get more from technology.

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Sigma 18-35mm F1.8 DC HSM - Digital Cameras
4.5 Outstanding

The Bottom Line

The Sigma 18-35mm F1.8 DC HSM delivers on its promise; it boasts the speed and sharpness of a prime lens, along with the convenience of a zoom.
Best Deal£556

Buy It Now

£556

Pros & Cons

    • Sharp.
    • Wide aperture.
    • Reasonable price tag.
    • Available for several camera systems.
    • Big.
    • No optical stabilization.
    • Some wide-angle barrel distortion.
    • Modest zoom ratio.

Sigma 18-35mm F1.8 DC HSM Specs

35mm Equivalent (Telephoto) 52.5 mm
35mm Equivalent (Wide) 27
Dimensions 4.5 by 3.1 inches
Lens Mount Canon EF-S
Lens Mount Nikon F
Lens Mount Pentax K
Lens Mount Sigma SA
Lens Mount Sony A
Optical Zoom 1.9 x
Stabilization None
Type Lens
Weight 1.8

Prior to the introduction of the Sigma 18-35mm F1.8 DC HSM ($799 direct) lens shutterbugs with APS-C D-SLR cameras had to make a choice when it came to lens functionality. You can go with a zoom lens and cover a range of focal lengths, but even top-end models only opened up to f/2.8. Or you can opt for a prime lens with a wide aperture, but it doesn't support zooming. Sigma aims to change that with this lens. It's impressively sharp, but it is a bit large compared with slower zooms or fast prime lenses, and its zoom range is modest at 1.9x. It stills earns high marks and our Editors' Choice award; the lens is an accomplishment, and the fact that it doesn't come with a sky-high price tag means that more photographers will actually be able to shoot with it.

The lens is currently available to order in Sigma, Nikon, and Canon mounts, but Sigma also plans on offering it for Pentax and Sony/Minolta cameras. It isn't compatible with full-frame bodies; the image circle only covers an APS-C sensor. This makes it an EF-S lens for Canon shooters, a DX lens for Nikon owners, and a DT lens for Sony D-SLR owners. The 18-35mm zoom range is roughly equivalent to 27-52.5mm in full-frame terms, which captures a wide angle view when zoomed out, and narrows to a standard-angle when zoomed all the way in. It doesn't offer quite the zoom range as the 18-55mm lens that likely came with your D-SLR, but it captures about four times the light on the wide end, and about  six times as much at the 35mm setting.

In addition to the obvious advantages when shooting in low light, using the lens at f/1.8 will allow you to capture images with a shallow depth of field, but just how shallow the focus is will depend on the focal length and your distance from your subject. When shooting at a wide angle it's difficult to get the bokeh look in your images, unless you are working fairly close to your subject. You'll get a shallower depth of field by backing up and zooming in. When conditions are right, the lens is able to capture photos with a smooth, blurry, out of focus area behind your subject.

Sigma 18-35mm F1.8 DC HSM : Sample Image

The 18-35mm is fairly large. It measures 4.8 by 3.1 inches (HD) and weighs about 1.8 pounds. The barrel is made of a composite material that feels sturdy and is cool to the touch, just like metal. There are two knurled control rings—the zoom ring is close to the base of the lens, and the manual focus ring is just behind the front element. The only control switch is a toggle to change between autofocus and manual focus mode. The filter thread accommodates a 72mm filter, and the lens is able to focus from 11 inches to infinity. A reversible lens hood and carrying case are included. Its size is not out of line when compared with the Pentax SMC DA Star 16-50mm F2.8 ED (IF) SDM($1,165.97 at Amazon) lens, which has a narrower maximum aperture but a longer zoom range.

I used Imatest to check the sharpness and distortion characteristics when paired with the Canon EOS Rebel T3i. The lens is impressively sharp at f/1.8, recording 2,383 lines per picture height using a center-weighted test; that's much better than the 1,800 lines we require for an image to be called sharp. Edges are also impressive, scoring an average of 1,868 lines, which would be impressive even for a prime lens. Stopping down to f/2.8 improves the overall score to 2,423 lines with edge performance just shy of 1,900 lines. Resolution at its widest focal length peaks at f/4; the lens manages 2,377 lines there.

Zooming to 24mm improves sharpness. At f/1.8 the lens scores 2,470 lines, and it peaks at f/4 at 2,690 lines. At 28mm the lens manages 2,457 lines at f/1.8 and improves to 2,562 lines by f/4. Zooming all the way in to 35mm delivers 2,399 lines at f/1.8 and peaks at 2,528 lines at f/4. Edge performance when zoomed in a bit is consistently good; better than 1,800 lines at every tested focal length and aperture.

The 18-35mm does show some distortion. At 18mm it records about 1.9 percent barrel distortion, which gives a slight outward curve to images. This is something that you can correct in software if it distracts from a shot. It's just on the cusp of being mild enough to ignore, but a few ticks with Lightroom's distortion slider adjustment tool will correct it. At 24mm the distortion is almost nonexistent, only 0.5 percent pincushion—which makes lines curve slightly inwards. You get a bit more of this, about 1 percent, at 28mm, and 1.2 percent at 35mm.

Sigma 18-35mm F1.8 DC HSM : Sample Image

To put this performance in perspective, compare the Sigma 18-35mm with the Canon EF-S 17-55mm f/2.8 IS USM($729.00 at Amazon) zoom. That lens is priced at just under $1,200 and features an aperture that is more than an f-stop slower. It does have a slightly longer zoom range and optical stabilization—which is lacking from the Sigma lens. It's also sharp, but not through the entirety of its zoom range. It's great at 17mm, where it notches 2,039 lines, and still good at 35mm where it hits 1,952 lines. Zoomed in at 55mm the score drops to a disappointing 1,516 lines, though it does sharpen up when stopped down. The Canon lens does a better job controlling distortion on the wide end; it shows only 1 percent barrel distortion at 17m, and its 1.6 percent pincushion distortion at 35mm and 55mm is not out of line with the Sigma.

But the Sigma 18-35mm F1.8 DC HSM captures twice as much light as an f/2.8 zoom and delivers more consistent sharpness than Canon's 17-55mm. When you factor in its attractive price, you have a lens that earns our Editors' Choice award. It's a great option for anyone who is looking to upgrade from an 18-55mm kit lens, as you are no longer required to choose between a lens with a very wide aperture or one that zooms. The only real knock on the 18-35mm is its rather modest zoom range. Photographers who are used to an 18-55mm lens may find themselves missing a bit of telephoto reach. But the range it does cover replaces three classic full-frame primes—a 28mm, 35mm, and 50mm—all at f/1.8 maximum aperture. That's an impressive feat for a zoom.

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Final Thoughts

Sigma 18-35mm F1.8 DC HSM - Digital Cameras

Sigma 18-35mm F1.8 DC HSM Review

4.5 Outstanding

The Sigma 18-35mm F1.8 DC HSM delivers on its promise; it boasts the speed and sharpness of a prime lens, along with the convenience of a zoom.

Get It Now
Best Deal£556

Buy It Now

£556

About Our Expert

Jim Fisher

Jim Fisher

Principal Writer, Cameras

My Experience

Images, and the devices that capture them, are my focus. I've covered cameras at PCMag for the past 14 years, which has given me a front row seat for the changeover from DSLRs to mirrorless cameras, the smartphone camera revolution, and the emergence of drones for aerial imaging. I have extensive experience with every major mirrorless and SLR system, and am also comfortable using point-and-shoot and action cameras. As a Part 107 Certified drone pilot, I’m licensed to fly unmanned aircraft systems (UAS) for commercial and editorial purposes, and am knowledgeable about federal rules and regulations regarding drones.

The Technology I Use

I use all of the major camera systems on a regular basis, swapping between Canon, Fujifilm, L-Mount, Micro Four Thirds, Nikon, and Sony systems. I still find time to use Leica M rangefinders and Pentax SLRs on occasion, too. I keep an iPhone 13 in my pocket for the rare occasions I'm not carrying a camera.

I'm not a brand-specific photographer. For product review photos, I swap between a Canon EOS R5 and a Sony a7R IV. I use Flashpoint and Godox TTL lights and Peak Design tripods, and I most often reach for a Think Tank or Peak Design backpack to carry equipment.

When it comes to computers, I'm an unapologetic Mac person and have been for the past 20 years. I write in Pages and use Numbers for spreadsheets. I currently swap between an Intel i9 MacBook Pro and an Apple Silicon Mac Studio for writing and use a calibrated BenQ 32.5-inch with the Studio for photo and video editing. I rely on a LaCie 6big RAID for media storage. I also keep a PC around for gaming, but please don't tell my Macs about it; they'll get jealous.

I split time between several different software apps depending on the type of editing I'm doing. For Raw image processing, Adobe Photoshop Lightroom Classic is my standard. I pair it with a LoupeDeck CT console to supplement my keyboard and trackpad, and I lean on RNI All Films 5 presets when I want to give an image a film look. I use Apple Final Cut Pro for video editing.

My first digital camera was the Canon PowerShot Elph S200, and my first DSLR was the Pentax *ist DL. I have a soft spot for antique film gear. I still use a 1950 vintage Rolleiflex Automat TLR and love trying mid-century Leica lenses on film and digital alike. I mainly use whatever's in front of me for review for digital snaps, but I pick up either my Leica M Typ 240 or Pentax K-3 III Monochrome when I want to step away from review work. In my downtime, I enjoy bird watching, reading, video games, and both good and bad movies, especially in the sci-fi and horror genres.

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