Reviews |Sigma 20mm F2 DG DN | Contemporary Review

Sigma 20mm F2 DG DN | Contemporary Review

Review

Price when reviewed

£649.99

$699
Check current price

Our Verdict

The Sigma 20mm F2 DG DN | Contemporary is a delightful lens that’s capable of producing high-quality images with plenty of sharp detail and minimal aberrations and distortion. It also feels like it’s made to last and comes the reassurance of weather-sealing. It would be great to see a de-click option for the aperture ring and a distance scale, but Sigma has produced a lovely little wide-angle lens with a bright aperture at a realistic price.

For

  • All-metal barrel and brass mount
  • Manual aperture ring
  • Weather-sealed

Against

  • Only available in Sony E-mount and the L-mount
  • No distance scale
  • Aperture ring can't be de-clicked

What is the Sigma 20mm F2 DG DN | Contemporary?

Sigma divides its lenses into three lines, Art, Contemporary and Sport. The Sigma 20mm F2 DG DN | Contemporary, which is also known as the 20mm F2 DG DN | C, sits in the second line. Sigma’s aim with its Contemporary lenses is to deliver uncompromised optical performance while still having a compact and lightweight form.

The Sigma 20mm F2 DG DN | C is also one of the company’s new I series lenses. These lenses have precision-cut aluminium barrels and weather-sealing for durability.

The description and specification of the Sigma 20mm F2 DG DN | Contemporary caught my interest from the outset so I was very keen to see what it can do.

Specification

  • Lens type: Full-frame wideangle prime
  • Announced: 9th February 2022
  • Available mounts: L-mount, Sony E-mount (FE)
  • Focal length: 20mm
  • Construction: 13 elements in 11 groups, with 1 FLD, 1 SLD, 3 aspherical elements
  • Coatings: Super Multi Layer, Nano Porous Coating (NPC)
  • Number of aperture blades: 9
  • Angle of view: 94.5°
  • Focus mechanism: Stepping motor
  • Closest focusing distance: 22cm
  • Maximum magnification ratio: 1:6.7
  • Maximum aperture: f/2
  • Minimum aperture: f/22
  • Filter size: 62mm
  • Supplied accessory: Petal lens hood, magnetic front lens cap, rear cap
  • Dimensions (diameter x length): L-mount: 75.5 x 109.5mm, Sony E-mount: 75.5 x 111.5mm
  • Weight: 370g
Sigma 20mm F2 DG DN | Contemporary review

Features

Although it is compact, the Sigma 20mm F2 DG DN | Contemporary is a full-frame lens. It’s specifically designed for use on mirrorless cameras and is available with either the L-mount or Sony E mount. Both of those mounts feature on full-frame and APS-C format cameras. On an APS-C format camera, the 20mm focal length effectively becomes 30mm.

As it has a focal length of 20mm, Sigma 20mm F2 DG DN | C is classed as an ultra-wide-angle lens, which makes it attractive for shooting landscapes and seascape. It’s large maximum aperture also adds to its appeal for astrophotography, interior and event photography.

Sigma constructs the 20mm F2 DG DN | C from 13 elements arranged in 11 groups. Amongst those elements there are 3 aspherical elements that are designed to maintain sharpness into the corners of the image without the lens being large. There’s also 1 SLD (Special Low Dispersion) element that reduces optical aberrations and 1 FLD (F Low Dispersion) element. The ‘F’ in F Low Dispersion denotes that the element is designed to have very high light transmission and offer similar optical performance to a fluorite element – but at lower cost. F Low Dispersion elements are also less brittle and easier to make than fluorite elements.

Sigma has also designed the 20mm F2 DG DN | C to suppresses sagittal coma flare, which makes highlights likes stars look triangular. Consequently, the lens should be a good choice for night sky photography.

Ghosting and flare are suppressed by Sigma’s Super Multi-Layer Coating and Nano Porous Coating.

Focusing is handled by a stepping motor that works internally, which means the lens stays the same length during focusing and the front element is static. That latter point is helpful for anyone thinking of using the 62mm filter thread to mount a graduated or polarising filter.

On a more disappointing note, Sigma hasn’t given the lens a focus distance scale. A scale could be useful for anyone shooting landscapes and wishing to use hyperfocal distance focusing.

Photographers with a Sigma, Leica or Panasonic camera with the L mount will find that the 20mm F2 DG DN | C is compatible with Sigma’s optional USB Dock UD-11. This can be used to customise some lenses and make firmware upgrades.

Sigma 20mm F2 DG DN | Contemporary review

Build and handling

The idea of an all-metal lens barrel is always attractive and it’s superbly delivered with the Sigma 20mm F2 DG DN | C. The lens has a delightfully high-quality appearance and it feels precision-engineered. I particularly like the deep knurling on the focusing and aperture rings, which is matched by the grooves on the petal-shaped metal lens hood. Yes, a metal lens hood, how often do you see that now?

And that’s not all that’s metal. Along with the usual plastic lens cap, Sigma supplies a metal, magnetic lens cap with the 20mm F2 DG DN | C. While the metal cap is a nice extra, I found it awkward to remove when the lens hood is in place. You have to reach down into the hood and get your fingernail under the edge of the cap to remove it. As a result, I used the plastic cap.

I tested the 20mm F2 DG DN | C on the Sony A7R IV, and they make a great partnership and the lens seems perfectly sized and weighted for the camera.

The aperture ring is sits roughly in the middle of the lens and it’s ideally located for rotating with the thumb and forefinger (or middle finger) of my left hand as I hold the camera from underneath.

If my thumb and middle finger are on the aperture ring, I can reach forward comfortably to the focusing ring with my forefinger to adjust the manual focus. The focusing ring moves very smoothly and there’s no need to grasp it, it can be moved with pressure from one finger. It’s easy to rotate without feeling too loose.

The aperture ring also has a nice action but its click stops make using your thumb and finger more comfortable. It also feels well-made and unlikely to be moved accidentally.

The aperture clicks are at very 1/3 stop, but the markings are at whole stop points from f/2 to f/22. As a photographer, the clicks are rather satisfying to feel, but they won’t please videographers and they can’t be avoided as there’s no ‘de-click’ control.

Along with the aperture settings the ring has an ‘A’ setting. When this is selected, the aperture is set and adjusted via the camera. There isn’t a lock to prevent the ring from being accidentally moved away from the ‘A’ point, but the distance between it and the nearest aperture setting is roughly double that of a full-stop adjustment, making it very distinct. That distance and the appropriate tension of the ring mean that it’s unlikely that it will be accidentally moved away from the A position.

Although there’s no ‘de-click’ switch, there is a focus switch which is nicely located near to where my thumb sits when I’m holding the camera. Consequently, you don’t need to use the camera’s menu or another switch to change between auto to manual focus mode.

Sigma 20mm F2 DG DN | Contemporary review

Performance

Shooting with the 61MP Sony A7R IV gives the resolving power of the Sigma 20mm F2 DG DN | Contemporary a good test – more than the 47MP Foveon sensor that Sigma states it uses to assess lens’ performance can. However, the 20mm F2 DG DN | C does a great job and there’s an excellent level of detail visible in my images.

The level of sharpness right across the frame is very impressive from wide-open (f/2) to about f/11. However, at f/16 the sharpness of the corners reduces a little and if you pixel-peep images that were shot at f/22, you’ll find the corners look rather soft. However, thanks to the short focal length there’s plenty of depth of field at wider apertures. For example, an aperture of f/8 and focusing at the hyperlocal distance of 1.69m, delivers an image that is sharp from 0.92m to infinity. Using an aperture of f/11, the closest point of sharp focus is 0.75m and the sharpness extends to infinity. It means that there shouldn’t be many occasions when you need to close down beyond f/11.

Nevertheless, the 20mm F2 DG DN | C has a closest focusing point of 22cm, and if you approach that at the wider apertures, it’s possible to blur the background significantly. And if you do so, you’ll find that the bokeh is very attractive with rounded rather than triangular small highlights.

I noticed very strong vignetting in the viewfinder when shooting at the widest apertures, however, the in-camera optical corrections or the correction profiles in Adobe Camera Raw (or other processing software) remove it. In fact, they are a little to zealous because they can make the corners look slightly too bright and I’m inclined to darken them a little at the processing stage.

The correction profiles, either in camera or in software, also do a great job of correcting the barrel-like bowing of straight lines that are seen without a profile.

I spent a lot of time using the 20mm F2 DG DN | C in bright sunshine and try to capture flare. However, even with the light passing over the front of the lens, it does a brilliant job of resisting it. Clearly, Sigma’s coatings are very effective.

Also, after scouring my images, I’ve concluded that the lens controls chromatic aberration very well.

The Sony A7R IV has an excellent autofocus system and as a result, most subjects I photographed were rendered sharp very quickly. As is often the case, it’s only when the subject is close to the nearest focusing point that you start to see some hunting. That’s when it would be nice to have a focus limiter switch. I was still usually able to get the subject sharp by turning towards something a little further away to get the camera and lens in the right zone, before reframing to focus on my intended subject.

Alternatively, it’s possible to focus manually and with the camera’s MF Assist option activated, the image is magnified as soon as the focus ring rotates. The camera also shows a distance scale in the viewfinder or on the screen to help guide the direction of the adjustment.

When the focus is adjusted from infinity to the closest focusing point, the view in the viewfinder changes as if the lens has zoomed in slightly. This effect is known as focus breathing and it could be problematic in videos with a subject moving towards or away from the camera. It is also likely to cause problems for anyone focusing stacking, but again, the extensive depth of field offered by the lens should make that unnecessary.

Sigma 20mm F2 DG DN | Contemporary sample images

Follow the link to browse and download sample images from the Sigma 20mm F2 DG DN | Contemporary on the Sony A7R IV.

Sigma 20mm F2 DG DN | Contemporary image gallery

Verdict

Unless I’m intending to shoot sport or wildlife, I naturally gravitate towards wide-angle lenses when I head out for a day with my camera. I like their perspective and the ability to go close to a subject while still including lots of background for context. I also like lenses with an aperture ring. I appreciate the speed of the adjustment that they allow and I somehow feel a little more connected with my photography. Consequently, the Sigma 20mm F2 DG DN | Contemporary caught my eye when it was announced and I’m delighted to find that it has such lovely build quality and is capable of delivering superb images.

With the exception of at the smallest aperture settings, there’s an excellent level of sharpness across the frame and chromatic aberration and flare are controlled extremely well. Unfortunately, the same cannot be said of focus breathing, but that’s not a deal breaker for photographers. It’s also a shame that the aperture ring can’t be de-clicked and there’s no focus limiter or distance scale, but I can forgive those points because of the lens’ small size, reasonable price and the quality of the images that it produces.

I hope that Sigma finds a way to be able to offer the 20mm F2 DG DN | C in a wider range of mounts, it would be great to see Canon RF and and Nikon Z mount version alongside the L-mount and Sony E versions.