05 Apr
Blog

Sigma 20mm F1.4 Art Review: More Than a Landscape Lens

Sigma 20mm f14 art criticism 9

Sigma 20mm F1.4 Art criticism: More than a landscape lens

"Not everyone loves wide-angle lenses, but Sigma's 20mm art made me a fan."

  • Rare combination of focal length and aperture

  • Impressively sharp at 1: 1.4

  • Professional build quality

  • Good price

  • Strong vignetting

  • No filter support

Wide-angle lenses are not sufficiently recognized for their versatility. If you think they are only for landscapes, give me the opportunity to change your mind. Although it's a landscape and astrophotography lens, I enjoyed using the Sigma 20mm F1.4 Art for portraits and product photos, and it was the perfect lens for wedding party dance shots (don't worry, that was a couple of months ago before, before social distancing).

This is not a new product – Sigma released it in 2015 – but when I got one borrowed for my Nikon D780 review, I liked it so much that I thought I should write it down. At 5 years old, this $ 900 lens is still the current champion in fast wide-angle prime numbers for Nikon and Canon DSLRs. It is also available for mirrorless Leica L or Sony E mounts, although it is a little more difficult to recommend for such cameras.

The design of the 20mm artwork raises some usability concerns that I will discuss later. However, if you're looking for the ultimate in low-light performance, no other 20mm lens is comparable to this. Considering the price to compete with the two 20mm f / 1.8 first-party lenses, this is an excellent buy.

design

Every photographic lens is a compromise exercise. Price, size, image quality and functions must be balanced to achieve a goal. With the Sigma Art series, it has always been important to deliver the best quality at a price that exceeds, or at least does not exceed, that of equivalent first-party lenses – regardless of size.

Weighing over 2 pounds, the 20mm art is certainly not a lightweight, but that's the price you pay for a 1: 1.4 bright aperture and an excellent optical formula. The 15 elements in 11 groups, including two aspherical elements, two of the “F” dispersion elements from Sigma and five special low dispersion elements, ensure sharp, aberration-free images with minimal distortion.

The lens body measures 3.6 inches in diameter and 5.1 inches long, including a built-in petal-style lens hood. I thought it would go well with the Nikon D780, but I'm not sure how to use it with a mirrorless camera.

This is a DSLR first lens. The mirrorless version includes an integrated "adapter" to compensate for the difference in the distance between the flange and residue, which makes the lens longer. Perhaps this wouldn't feel too out of place with a powerful Panasonic S-series camera, but I don't know how comfortable it would be with a smaller, lighter Sony Alpha-series camera. Given that Sony recently launched the excellent FE 20mm f / 1.8G, there's a solid alternative for E-mount shooters.

The Sigma offers a minimalist exterior with a wide, knurled focus ring and a window removal scale that give it a first-class appearance. The AF / MF switch is the only other control point. There is neither a stabilizer to turn on or off – not that I would expect with a lens so wide and fast – nor an aperture click switch like the one we see on Sony's 20mm f / 1.8 and Sigma's own 35 mm saw F1. 2 Art.

The bulbous front element of the Sigma means that you cannot use a standard screw-on filter. This can be a problem for landscapes if you want a polarizer or neutral filter. Professionals and other seasoned shooters may not mind using a filter adapter with large drop-in filters, but for the rest of us, the lack of native filter support could be a reason to consider an alternative lens.

Autofocus

With the Hyper Sonic Motor (HSM) from Sigma, the 20 mm F1.4 graphics can be quickly focused in the viewfinder as well as in the live view. If you switch from the foreground to the background, you can feel the torque of the motor when it is switched on. Still, it makes very little noise.

Continuous autofocus performance was also very good – no doubt supported by the intelligent focusing algorithm used in the D780 – and kept pace with a cyclist heading towards me. It was also decent in a dimly lit lobby, although the camera's focus sensor was probably the bigger limiter (the D780 is good for -3 EV with the viewfinder).

However, there is a big problem with autofocus, at least when shooting through an optical viewfinder. After unpacking, my copy of the lens was focused pretty dramatically. Customers have reported similar issues in user reviews. This isn't exactly new to Sigma – I also found the problem when reviewing the 105mm F1.4 art – but it seems to be something the company is using with newer lenses like the 40mm art, which I have now recorded seems to be under control on Canon and Nikon with no problems.

Fortunately, most modern DSLRs offer the ability to adjust the focus behavior of a lens (the Nikon D780 can do this automatically using the AF fine-tuning feature that uses focus information from live view to correct viewfinder performance). You can also purchase the Sigma USB lens dock to program focus settings directly into the lens firmware.

While this problem is easy to fix, the customer must know how to recognize it. I can imagine someone buying and returning this lens because they just thought it wasn't sharp. That couldn't be further from the truth.

picture quality

When I realized what was happening with the autofocus and figured out how to fix it, the Sigma 20mm Art thrilled me with incredibly detailed images and surprisingly rich bokeh (which is usually not the case with such wide lenses). There seems to be little to no sacrifice in sharpness when opened wide at 1: 1.4.

Distortions are certainly there, but they are fairly mild and can be easily corrected in the post without much harvest.

However, vignetting could be the real problem here, especially if you want to use this lens for astrophotography. Photography in the night sky usually requires a bright aperture and even focus and exposure across the frame. At 1: 1.4, the 20mm type vignettes are exactly what you would expect from a 20mm 1: 1.4 lens. It is serious.

I don't mind that with other types of photography, but with astrophotography, if you are already shooting at high ISO values, correcting the vignette in the post by lightening the corners only leads to more noise. Maybe it's not a big deal – I've seen fantastic astro shots from other photographers who used this lens – but it's something to watch out for.

Our opinion

The 20mm focal length may be of limited use to most photographers, but the Sigma 20mm F1.4 Art has made me a fan. I really enjoyed taking pictures with it, much more than I thought, especially for subjects that don't expect a lens as wide as portraits and products. Sometimes a new perspective is enough to refresh your creativity. Literally.

As an older model, the 20mm art has shown Sigma to improve auto focus accuracy on newer lenses. I would love to see a mirrorless redesign of this lens, as Sigma did for the 14-24mm f / 2.8 type. For Canon and Nikon DSLR shooters, however, this is still the wide-angle prime to beat.

Is there a better alternative?

Certainly not for Canon DSLRs. Nikon manufactures a 20mm f / 1.8 that is significantly lighter (12oz) and accepts 77mm filters. It's also quite a bit cheaper at the time of this writing, thanks to instant discounts that get it to just under $ 720. However, the sigma is sharper and brighter, and I expect the additional $ 180 to be worth it.

For Sony shooters, the FE 20 mm 1: 1.8 G is worth a look. It weighs just over 13 ounces, uses 67mm filters, and has an aperture ring with de-click controls. It is also visually excellent. At $ 900, however, you save no money and sacrifice the additional 2/3 blink collection that the f / 1.4 aperture of the Sigma offers you. For most people, however, this is a worthy trade for a lens that better fits Sony's smaller cameras.

How long it will take?

The 20mm art that was released in late 2015 is 5 years old and remains one of the best wide angles on the market. I wouldn't be surprised if Sigma introduces a mirrorless version in the not too distant future, but anyone who buys this lens for a DSLR today should have no problem working with it for many years.

Should you buy it

If you record a Canon or Nikon DSLR, absolutely. If you're shooting a mirrorless L-mount camera, maybe. If you're shooting a Sony E-mount camera, this is probably not the case – choose the FE 20mm f / 1.8 from Sony.

Editor's recommendations




29 Mar
Blog

Sony FE 20mm f/1.8 G Lens Review: The Perfect Astro Lens?

Sony Fe 20mm F18 test lens 7771

Sony FE 20mm f / 1.8G lens test: an excellent landscape lens

"With maximum sharpness and minimal distortion, the 20 mm lens from Sony is an almost perfect astrophotography and landscape lens."

  • Outstanding sharpness

  • Small to no aberrations

  • Light

  • Aperture de-click switch

  • Weatherproof

  • Slight barrel distortion and vignetting

With the exception of third-party manufacturers, the Sony FE 20mm f / 1.8G is the widest full-frame E-mount prime lens to date. It's designed to take more of the scene and offers a 94-degree angle of view – phone photographers can imagine it is between the wide-angle and ultra-wide-angle lenses of an iPhone 11 – but adjusts this field of view with a large f / 1 , 8 aperture for excellent low-light performance.

While the focal length and aperture are clear in the name of the lens, other features from Sony such as the "advanced optical design" and the "Dual XD Linear Motor" have to be decoded. (I'll come to that.)

But are these features worth nearly $ 900? Thanks to superior sharpness and minimal distortion, I have to say yes. This is still a niche lens, but its jargon-packed list of features is more than just marketing hype.

Design and specifications

The FE 20mm f / 1.8 is part of Sony's high-end G-series (but not the high-end GM-series) and is housed in a weatherproof, lightweight housing that fits on the A7R IV which I served as a test camera, this review felt at home. These two linear autofocus motors help the lens adjust the performance of modern Alpha series housings, while a dedicated aperture ring with a click switch enhances its appeal for serious video shooters.

The lens feels sturdy and well built. The barrel isn't made of metal, but that helps keep the weight at a reasonable 13 ounces. With a length of 3.5 inches, it doesn't take up much space in the camera bag and accepts modest 67mm filters.

What is not obvious when looking at the lens is the optical design, which consists of 14 elements in 12 groups with an aperture of nine wings that stops up to 1:22.

An aperture ring offers direct control of the aperture without having to rely on a camera-based dial. This takes getting used to, but feels just like how you naturally hold a camera in two hands.

The aperture ring is not just about ergonomics. With the de-click switch, the aperture settings can be adjusted silently and continuously, which is important for video recording. I definitely prefer to enable the click for still images as you can feel how much you've adjusted it without looking. (The aperture value is still displayed in the electronic viewfinder, but the click only feels more reassuring.)

In addition to the aperture ring and the de-click switch, there is a focus lock button and a switch in the lens barrel with which you can easily switch from auto focus to manual mode. A standard focus ring is located on the front of the lens.

Autofocus

This is where the dual XD linear motor system comes in, which is said to generate fast and quiet auto focus. My experience matched these claims. The auto focus is pretty quiet. It is not silent, but it does not distract you when you take pictures in a sensitive environment such as a wedding ceremony.

The speed of the autofocus was in line with the expectations we had of the A7R IV – fast and accurate, only struggling with subjects that most cameras struggle with, such as shiny objects or where there is not much contrast.

The 20 mm focus very close to the front of the lens, about 7 inches. With the large focal length, this is not enough for real macro functions, but I did not expect the generous 0.2x magnification. For a wide-angle lens, this close-up opens up a number of creative possibilities for a variety of subjects.

picture quality

Note that 20 mm is an unusual focal length – 24 mm is much more common for a prime number, since larger angles are usually covered by zooms, e.g. B. the FE 16-35 mm f / 2.8 from Sony. The focal length is ideal not only for taking wide views, but also for exaggerating the distance between objects, while the bright aperture of 1: 1.8 simply cannot be achieved by zooming.

The lens has some barrel distortion towards the edges, but less than expected with a wide-angle lens. Lines near the edges of the frame are gently curved towards the corners, but this can easily be attached to the post.

Vignetting is also a common problem with wide-angle lenses, especially with such large apertures, but the Sony 20mm only had a very slight darkening in the corners. The vignette was completely removed by a slight adjustment of +5 in Lightroom.

However, the resolution is even more impressive. The sharpness was excellent in the middle, even wide open, and really showed what the 61 megapixel A7R IV can do. Lowering the aperture brought a slight improvement, but if you want that dreamy, shallow depth of field, you don't have to worry about sacrificing focus to get it. The edges had only a slight drop in sharpness, which is probably not recognizable in real pictures.

Where the lens really shines is in astrophotography. This is certainly a photographic discipline in which both bright apertures and wide angles are required and where sharpness is of the utmost importance. Stars are represented as tiny pinpricks of light without sagittal coma flickering, even towards the edges of the frame. Together with the resolution of the A7R IV, the lens helped capture an abundance of sharp stars.

Small light sources do not suffer from the usual flares, while larger light sources – such as the sun or the moon – create starbursts. But the flare is well controlled overall in the FE 20 mm, and even hard light didn't cause much of a problem. Occasionally, a starburst was paired with a rainbow arch or a slight color shift, but nothing big. Chromatic aberration also does not appear to be present.

Wide angles are generally not thought of for their bokeh, but the FE 20mm f / 1.8 looks great here. With an aperture of nine sheets, even a stopped recording creates soft, circular blur patterns. I couldn't see any "onion rings" or other strange shapes that bokeh fans like to criticize.

For videos, the lens produced more of the same with sharp details and well-controlled stray light. The clicked aperture is very impressive here; I could hear my own breathing, but no mechanical noise when I set the aperture while recording.

Our opinion

The wide angle, the fast aperture and the high-end optics ensure an excellent mix of the Sony FE 20mm f / 1.8G. The sharpness is excellent, aberrations are minimal or nonexistent and all the things that wide-angle lenses do most struggle – like barrel distortion and vignetting – are minor and barely noticeable on most shots.

For $ 898, this is certainly not a budget prime. But for photographers who regularly pull out a wide angle, the high-quality workmanship and the impressive optics are probably worth it. The lens is ideal for astrophotography, landscapes and any other picture that needs a broad perspective.

Is there a better alternative?

The focal length of 20 mm is not very common, and for e-mount shooters it depends on this Sony that Sigma 20 mm 1: 1.4 DG HSM Art.or just with a zoom.

The Sigma is an excellent lens, but some users complain about corner distortion when shooting stars. Designed as a DSLR lens, it weighs twice as much as the Sony. In addition, there is not the usual financial advantage of a third-party provider, since both lenses cost the same.

However, the Sigma has a brighter aperture of 1: 1.4 for shots where the last bit of light is important. The Sony 20mm is probably the better option for most, as the 1: 1.4 advantage over 1: 1.8 is pretty small, but the size and weight difference is big.

How long it will take?

The Sony 20mm is well built, so the lens should last for several years, apart from a major disaster. Lenses typically have long product lifecycles, so we wouldn't expect a replacement for many years.

Should you buy it

Yes. If you need a bright wide-angle prime in your kit, the Sony FE 20mm f / 1.8G offers excellent quality in a light, durable lens that's not too expensive.

Editor's recommendations