The Sigma 14-24mm f2.8 DG DN Art is an ultra-wide angle zoom lens designed for full-frame mirrorless cameras and available in the Sony E and Leica L mounts, the latter working on Leica, Panasonic and Sigma L-mount bodies. Like other 14-24mm lenses, it delivers wide to ultra-wide coverage that’s ideal for dramatic urban and natural landscapes, while maintaining a bright and constant f2.8 focal ratio across the range.
The Sigma 14-24mm f2.8 DG DN Art was announced in July 2019 and is currently listed at 1450 EUR / 1399 USD / 1299 GBP. PS – if you’re interested in the other Sigma DG DN Art lenses check out our in-depth reviews: Sigma 35mm f1.2 DG DN Art review, Sigma 24-70mm f2.8 DG DN Art review, Sigma 85mm f1.4 DG DN Art review, Sigma 105mm f2.8 DG DN Macro Art review.
Facts from the catalog
Let’s compare the Sigma 14-24mm f2.8 DG DN Art (“Sigma DN” for short) to the Sony FE 12-24mm f4.0 G (“Sony f4.0 G”), Sony FE 12-24mm f2.8 GM (“Sony f2.8 GM”), and Sigma 14-24mm f2.8 DG HSM Art (“Sigma HSM”) which was designed for DSLRs but still can be used via Sigma’s MC-11 mount-converter on a Sony mirrorless camera. As usual I’ve rated the features with a [+] (or [++]), when it’s better than average or even state of the art, a  if it’s standard or just average, and [-] if there’s a disadvantage.
Size (diameter x length): All four lenses have a built-in lens hood and don’t change their length when zooming. At 86 x 132mm (3.4 x 5.2in.) the Sigma DN is longer than the Sony f4.0 G at 87 x 117mm. But both the Sony f2.8 GM at 97 x 137mm and the Sigma HSM at 96 x 132mm are bigger lenses, the mount-converter adding another 26mm to the length of the Sigma HSM. 
Weight: At 797g (28 oz.) the Sigma DN is 234g heavier than the Sony f4.0 G at 563g but still a bit lighter than the Sony f2.8 GM at 847g. The Sigma HSM is much heavier at 1122g plus an estimated 100g for the mount-converter. 
Optics: The Sigma 14-24mm f2.8 DG DN Art has 18 elements in 13 groups including 6 special dispersion elements and 3 aspherical elements. This is similar to the other lenses in this comparison. To reduce reflections causing flare, glare and ghosting the Sigma DN employs Nano-coating. It also has fluorine-coating on the front element to repel water, dust, and dirt and make cleaning easier. [+]
Closest focus distance is 0.23m (0.91ft.) at 24mm focal length with a magnification of 1:5.1 which is similar to the Sigma HSM. This results in a working distance of only 8cm. The Sonys achieve about 1:7 at 28cm focus distance. A magnification of 1:10 is achieved at around 0.35m focus distance with all four lenses. [+]
Filter-thread: None of the four lenses in this comparison offer filter-thread – their bulbous front elements prevent that. So you need to get some non-standard mounting system and a new set of filters. Or use gel filters in a rear filter holder on the Sigma DN (see image below) and the Sony f2.8 GM. Keep in mind though that gels cannot be rotated which precludes the use of polarizers. Sigma supplies a template with the lens to cut out the gels. But you can also buy ready-made rear lens filters. 
Image stabilization: All four lenses in this comparison have no optical image stabilization. But the Sony A7 or Panasonic DC-S1 camera bodies provide built-in sensor-shift stabilization. 
Auto focus: Yes with built-in AF drive. Manual-focus override is by simply turning the dedicated focus ring at the front of the lens. It has a variable gearing (like many lenses designed for mirrorless cameras) which allows for very precise manual focus when turned slowly but cannot be switched to linear gearing. Which makes smooth focus pulling for videographers pretty hard. Same with the Sonys. The three lenses designed for mirrorless cameras also have an extra button which can be assigned many different functions e.g. AF-lock. The Sigma HSM has the usual direct linear coupling that is typical for lenses designed for DSLRs – and shows the focus distance in a small window. [+]
Lens profile: The lens comes with a lens profile for vignette-, CA- and distortion-compensation which can be controlled from the camera. That’s the same as with the Sonys. With the Sigma HSM you have to rely on the profiles supplied e.g. in Adobe’s software. [+]
Covers full frame/FF or smaller. Same with the other three lenses. [+]
Price: 1450 EUR (incl. 16% VAT) / 1399 USD / 1299 GBP. The Sony f4.0 G currently goes for 1550 EUR / 1670 USD / 1400 GBP, the Sony f2.8 GM is at 3300 EUR / 3000 USD / 2900 GBP and the Sigma HSM at 1280 EUR / 1199 USD / 1129 GBP. 
Aperture ring: None of the four lenses in this comparison has an aperture ring. 
The lens comes with a padded pouch but no straps. [+]
Sigma’s service can change the mount of the lens between Sony’s E-mount and L-mount (at a cost). This is a unique feature that no other manufacturer offers. [++]
Sealing: yes, a rubber grommet at the lens-mount plus further special weather-sealing throughout the construction, just like the other three lenses. [+]
The score in the “features-department” is 0[-]/6/9[+] The Sigma 14-24mm f2.8 DG DN Art offers a nice feature set and the unique option to get the lens-mount swapped. The biggest complaint compared to some of the rivals here is that it doesn’t zoom wider than 14mm, but while 12mm will capture a wider field, 14mm still delivers enormous coverage. Another issue, common to most ultra-wide zooms, is needing some non-standard mounting system if you’re going to use front filters.
If you want to cover the range of focal lengths from 14mm to 24mm there are really only two alternatives to the Sigma 14-24mm f2.8 DG DN Art for E-mount and none for L-mount:
- Sony has the FE 12-24mm f4.0 G from 2017 and the FE 12-24mm f2.8 GM. Both lenses start at 12mm focal length giving an 8 degrees wider view on the short end than zoom lenses starting at 14mm. The Sony f4.0 G is only slightly more expensive than the Sigma DN but its focal ratio is one stop slower. And the Sony f2.8 GM has the same bright f2.8 focal ratio but is more than twice the price of the Sigma DN.
Other alternatives cover different focal lengths like the Panasonic Lumix S PRO 16-35mm f4.0 or the very expensive Leica Super-Vario-Elmar-SL 16-35mm f3.5-4.5 ASPH (both for L-mount). Or the manual focus Laowa 10-18mm f4.5-5.6 which is available for E- and L-mount and is currently the only full frame zoom lens starting at 10mm focal length with a recti-linear projection. Or you use older DLSR designs via mount adapter.
Here is the angle of view that the Sigma 14-24mm f2.8 DG DN Art covers with its 1.7x zoom compared to the 2x coverage of the Sony FE 12-24mm f4.0 G:
Focus and zoom
Focus accuracy and repeatability is critical to consistently produce sharp shots. Repeatability (the accuracy of focus on the same subject after repeated focus-acquisition) of the Sigma at 24mm focal length is good (measured 98.2% in Reikan FoCal) with no outliers over a series of 40 shots. There is a bit of focus variation whether the lens focuses from a closer distance or from infinity and I had some cases of hunting. At 24mm focal length the lens focuses in around 0.7 sec from infinity to 0.35m (1:10 magnification), which is OK but slower than the Sony FE 12-24mm f4.0 G which took only 0.5 sec.
The zoom ring turns through 70 degrees the other way around than Sony users are used to and has a 14mm wide rubber surface with a good grip. It can hardly be operated with one finger as it needs more force than the Sony FE 12-24mm f4.0 G. The focus ring at the front is 20mm wide and moves smoothly.
AF-operation of the Sigma is inaudible from the outside or if you record video with the built-in microphone. Same with the Sony FE 12-24mm f4.0 G.
As you pull focus, you’ll hardly notice any focus breathing: When I adjusted the focus from infinity to 0.35m on the Sigma I measured a 1% decrease in magnification at 24mm and 14mm focal length. This is similar to the Sony FE 12-24mm f4.0 G.
The Sigma zoom lens is parfocal: When I focused the lens at 24mm and zoomed back to 14mm focus stays on the same spot. Same with the Sony FE 12-24mm f4.0 G.
Next check out my quality results!