Sigma has announced a pair of new fast wide-angle prime lenses for E-mount and L-mount full-frame mirrorless cameras. The Sigma 20mm F1.4 DG DN Art is the world’s first and only 20mm F1.4 lens designed exclusively for full-frame mirrorless cameras, and the Sigma 24mm F1.4 DG DN Art is a premium wide-angle prime lens at a very reasonable price.
The new 20mm F1.4 DG DN Art and 24mm F1.4 DG DN Art are the two widest lenses in Sigma’s DG DN Art F1.4 lens range, joining the existing 35mm F1.4 DG DN Art and 85 mm F1.4 DG DN Art lenses that were released in 2021 and 2020 respectively.
Sigma 20mm F1.4 DG DN Art (left) vs. Sigma 24mm F1.4 DG DN Art (right)
We’ve worked with virtually each of the two new prime lenses using a Sony A7R IV camera, and the lenses are very impressive. While each shares a common aesthetic and some features and fits a somewhat similar use case, we’ll look at them individually, starting with the Sigma 20mm F1.4 DG DN Art.
Sigma 20mm F1.4 DG DN Art
The Sigma 20mm F1.4 DG DN Art is the mirrorless follow-up to the Sigma 20mm F1.4 DG HSM Art. Make no mistake though, the new mirrorless version isn’t just a reskin. This is a new lens. It is designed exclusively for mirrorless cameras and is the only lens of its kind available for full-frame mirrorless cameras. It features the largest double-sided aspherical element Sigma has ever put into a lens, while maintaining an 82mm filter thread, which is impressive for a fast lens of this width.
Despite the large front element, and is large, the lens is not that heavy nor does it feel too big when mounted on the Sony A7R IV. The lens weighs 635 grams (22.4 ounces), which is 262 grams more than the Sony 20mm F1.8 G and 190 grams more than the Sony 24mm F1.4 GM. Of course, the Sony 20mm, while a great lens, isn’t as fast as the Sigma 20mm F1.4, and the 24mm F1.4 GM isn’t as wide.
Sigma 20mm F1.4 DG DN Art on Sony A7R IV
The Sigma 20mm F1.4 Art is 111.2 mm (4.4 inches) long without the removable petal-shaped lens hood, and its maximum diameter is 87.8 mm (3.5 inches). However, most of the lens barrel is slightly narrower than this as the maximum diameter is 87.8mm due to the filter thread area at the front of the lens.
The lens looks like any new Sigma Art lens, meaning it is a semi-flat black lens with high quality materials and construction. The lens includes a manual aperture dial with full aperture stops indicated (F1.4, 2, 2.8, 4, 5.6, 8, 11 and 16) and markings for every one-third aperture between F1.4-16. There’s also an “A” position that lets you control the aperture through the camera, either with a dial, or by letting the camera choose aperture in semi-automatic or fully automatic shooting mode. The lens includes an aperture dial lock switch.
Sigma 20mm F1.4 DG DN Art on Sony A7R IV
Almost half of the lens barrel consists of a wide focusing ring with a knurled rubber surface. The focus ring has a tight rotation, providing a decent amount of resistance. It feelings great. As for usefulness, it depends somewhat on the camera and your settings since it’s a wire lens focus, but I think the overall manual focus experience is pretty good. There’s also a manual focus lock button, which is great so you don’t accidentally change the focal length when using manual focus. This is especially useful when doing astrophotography. Unfortunately, the weather didn’t cooperate during my work with the new Sigma lenses, but this lens looks amazing for astrophotography on paper. The lens also includes a de-click switch for the aperture ring, a focus button, and a focus switch.
Lens hoods aren’t a hot topic, but it’s worth noting that the LH878-04 petal hood that comes with the Sigma 20mm F1.4 DG DN Art lens is top notch. It feels high quality and works well. The lens also comes with a nice soft zippered case. It’s a nice case and it’s great to see lenses, especially those under $1000, come with a good case.
Sony A7R IV with Sigma 20mm F1.4 DG DN Art lens at F1.4, 1/40s, ISO 100. This image has been edited.
Let’s move on to image quality. The Sigma 20mm F1.4 DG DN Art features 17 elements in 15 groups, including a pair of SLD elements and 3 aspherical lens elements. I mentioned that one of these aspherical elements is the largest double-sided aspherical element that Sigma has ever put in a lens, which is pure trivia.
Sony A7R IV with Sigma 20mm F1.4 DG DN Art lens at F8, 20s, ISO 400. This image has been edited.
The quality of the resulting image is good. The lens is sharp, although its performance at F1.4 leaves a bit to be desired. However, although the lens is noticeably softer at F1.4 than at F2 and F2.8, sharpness is still quite good. As far as aberration and flare control goes, the lens is great. There is a slight purple fringing, but that’s about it, and it’s only apparent in particularly difficult situations.
Sony A7R IV with Sigma 20mm F1.4 DG DN Art lens at F1.4, 1/3200s, ISO 100. This image has been edited.
Impressive quality requires a suitably robust autofocus system. The Sigma 20mm F1.4 DG DN Art does well here as well. The lens uses a stepper motor that provides fast and mostly quiet focusing. The lens supports DMF, AF+MF, AF Assist and other Sony focus functions when using the E-mount version. The minimum focal length of the lens is 23 cm (9.1 inches), resulting in a maximum magnification ratio of 1:6.1. Doesn’t focus very close. Still, it’s good enough for focusing on close-up foreground elements in landscape shots, if that’s something you’re into.
Sony A7R IV with Sigma 20mm F1.4 DG DN Art lens at F8, 1/250s, ISO 100. This image has been edited.
Overall, the Sigma 20mm F1.4 DG DN Art is an excellent, high-quality, fast ultra-wide-angle prime lens. Not only is it one-of-a-kind for full-frame mirrorless cameras, it’s also a lot good lens. Plus, it’s $899, which is a very reasonable price. The Sigma 20mm F1.4 DG DN Art will be available in late August for E-mount and L-Mount systems.
Sigma 24mm F1.4 DG DN Art
The other new fast wide-angle prime is the Sigma 24mm F1.4 DG DN Art. Unlike the 20mm F1.4 DG DN Art, the 24mm F1.4 DG DN Art has competition from other brands, including Sony itself with the FE 24mm F1.4 GM. However, like the 20mm lens, Sigma is aggressively priced with its new 24mm F1.4 prime. The Sigma 24mm F1.4 DG DN Art is $799, undercutting Sony’s G Master lens by $600.
What about the build quality? Like the 20mm F1.4, Sigma uses a thermally stable composite (TSC) for its 24mm F1.4 DG DN Art lens. Also, like the 20mm lens, the 24mm lens includes dust and splash resistance.
Sigma 24mm F1.4 DG DN Art on Sony A7R IV
In terms of size and weight, the 24mm F1.4 DG DN Art is quite a bit smaller and lighter than the 20mm F1.4 DG DN Art. That’s not to say either lens is big or heavy, but the 24mm is noticeably smaller. The maximum diameter is 75.7 mm (3 inches) and the lens is 95.5 mm (3.8 inches) long. The lens has a 72mm filter thread. The 24mm F1.4 DG DN Art weighs 520g (18.3 oz.), which is 115g lighter than the 20mm F1.4 DG DN Art. Compared to the Sony 24mm F1.4 GM, the Sigma 24mm F1.4 DG DN Art is 75g (2.6oz) heavier and several millimeters longer. Both lenses are similar in diameter, although the Sony GM lens uses a 67mm filter size.
Sigma 24mm F1.4 DG DN Art on Sony A7R IV
In terms of style, the 24mm F1.4 DG DN Art looks a lot like a 20mm lens, only smaller. Includes wide focus ring, AF/MF switch, MFL lock, aperture ring de-click switch and aperture ring lock switch. The aperture ring features the same markings from F1.4 to F16. Speaking of aperture, the 24mm lens also features an 11-blade rounded aperture diaphragm. Incidentally, both lenses include a rear filter holder, so you can use rear-mounted filters without worrying about distortion or vignetting. The lens also comes with a nice petal-type hood and the same style of soft case, although, like the lens, the case itself is smaller than the one that comes with the Sigma 20mm F1.4 lens.
Sony A7R IV with Sigma 24mm F1.4 DG DN Art lens at F1.4, 1/8000s, ISO 160. This image has been edited.
The Sigma 24mm F1.4 DG DN Art features 17 elements organized into 14 groups. Special elements include two FLD elements, one SLD element and four aspherical lens elements. The lens is designed to minimize flare and ghosting and provide strong sharpness throughout the frame, even when shooting wide open. The lens lives up to these promises and offers excellent image quality.
Sony A7R IV with Sigma 24mm F1.4 DG DN Art lens at F1.4, 1/4000s, ISO 100. This image has been edited.
The 24mm F1.4 lens performs better at F1.4 than the new 20mm fixed lens. The lens is very sharp when shooting wide open, at least in the center of the frame. You need to stop the lens down to F2.8 or F4 to get good performance in the corners on a full-frame camera. Like the 20mm lens, the 24mm lens exhibits good control over aberrations and flare. The lens also has minimal distortion, at least with lens corrections applied.
Sony A7R IV with Sigma 24mm F1.4 DG DN Art lens at F8, 1/40s, ISO 100. This image has been edited.
Like the Sigma 20mm F1.4 lens, the Sigma 24mm F1.4 offers great autofocus performance via a stepper motor system. The lens is compatible with Sony’s various autofocus and lens aberration correction features. The lens does not focus very close. It focuses up to 25 cm (9.9 inches) away, resulting in a maximum magnification ratio of 1:7.1. In case you’re curious, it’s almost identical in close-focus performance to Sony’s 24mm F1.4 GM lens.
Sony A7R IV with Sigma 24mm F1.4 DG DN Art lens at F11, 1/8s, ISO 100. This image has been edited.
The Sigma 24mm F1.4 DG DN Art is a great lens. While it’s not as exciting as Sigma’s new 20mm F1.4 DG DN Art lens because it’s not a truly unique offering, it doesn’t take anything away from the 24mm F1.4 Art lens. It provides great sharpness, impressive autofocus and good build quality, all at a very nice price of $799. The Sigma 24mm F1.4 DG DN Art will be available for E-mount and L-mount at the end of August.