20mm F1.4 DG HSM

Design detail

The world's first F1.4 ultra-wide-angle lens for full-frame DSLRs

Incredible rendering performance delivers unprecedented visual experiences. Enjoy enhanced control of light and composition. SIGMA has extensive experience in leveraging its advanced design capabilities and leading-edge technologies to craft large-aperture prime lenses that bring out the full potential of ultra-high-megapixel DSLRs. As its latest achievement in this category, SIGMA has created an ultra-wide-angle lens with F1.4 brightness. With a focal length of 20mm and F1.4 aperture, this lens delivers outstanding large-aperture brightness and bokeh, delivering unprecedented visual experiences. Allowing the photographer to leverage the perspective provided by the wide -angle and the shallow depth of field provided by the large aperture, this lens is ideal not only for such ultra-wide-angle subjects as landscapes and starry skies, but also for snapshots in low light, indoor photography, portraits with a natural bokeh effect, and much more.

Advanced technologies make a 20mm F1.4 lens possible

World's first* 20mm F1.4 lens—thanks to advanced large-diameter aspherical lens manufacturing technologies

To offer an ultra-wide-angle 20mm focal length and F1.4 brightness at wide-open aperture, this lens incorporates a large double aspherical lens 59mm in diameter. Lenses of this type had been considered extremely difficult to manufacture, but SIGMA took on the challenge to realize an F1.4 ultra-wide-angle lens that fulfills the strict performance requirements of the SIGMA Art line. What made this breakthrough possible were SIGMA’s advanced manufacturing technologies, which the company has developed over time by producing a wide range of ultra-wide-angle and large-aperture lenses. For example, milestone lenses such as SIGMA 12-24mm F4.5-5.6 EX DG ASPHERICAL HSM, SIGMA 8-16mm F4.5-5.6 DC HSM, and SIGMA 18-35mm F1.8 DC HSM | Art were completely original products that helped SIGMA develop outstanding design and production know-how and its current high-precision, high-efficiency production system. In turn, these advances made possible the new SIGMA 20mm F1.4 DG HSM | Art. Moreover, SIGMA’s advanced optical design minimizes distortion, transverse chromatic aberration, sagittal coma flare, and the reduction of brightness toward the edges of the image. Delivering top performance even at wide-open aperture, this lens can be considered the culmination of SIGMA’s Art line.

*Among interchangeable lenses for digital cameras with 35mm full-frame image sensors (SIGMA research as of October 2015)

Minimized chromatic aberrations World's first* 20mm F1.4 lens—thanks to advanced large-diameter aspherical lens manufacturing technologies

This lens minimizes chromatic aberrations, a common issue in large-aperture ultra-wide-angle lenses. It features two FLD (“F” Low Dispersion)* glass and five SLD (Special Low Dispersion) glass elements to minimize transverse chromatic aberration, which is mainly visible around the edge of the image. The optimized lens power distribution helps minimize axial chromatic aberration. As a result, this lens delivers high image quality in every situation without color smearing, and its rendering performance is consistently sharp with high contrast.

*FLD glass is ultra-low-dispersion glass that offers performance of the highest level. Highly transparent, its refractive index and dispersion are extremely low as compared to conventional types of glass. It offers characteristics very similar to those of fluorite, which is valued for its high anomalous dispersion. These characteristics minimize residual chromatic aberration (secondary spectrum), which cannot be corrected by ordinary optical glass, while helping to produce sharp, high-contrast images.

Minimized distortion

Distortion is a common issue in wide-angle lenses, and it is not possible to correct it simply by changing the aperture value. For this reason, a lens must be designed from the start to minimize this issue. By adjusting the incidence angle of light starting with the first lens element and incorporating optimally positioned aspherical glass elements, the SIGMA 20mm F1.4 DG HSM | Art lens minimizes distortion throughout the entire image.

Designed to minimize flare and ghosting

From the start of the design process, SIGMA measured flare and ghosting to establish an optical design that is resistant to strong incidental light sources such as backlight. At the prototyping stage, SIGMA used not only simulations but actual photographic experiments to assess flare and ghosting under multiple criteria, identify the causes of these issues under a wide range of situations, and take measures to mitigate them. In addition, SIGMA’s Super Multi-Layer Coating helps further reduce flare and ghosting and provide sharp, high-contrast images even in backlit conditions.

The ideal high-speed lens for snapshots and much more

Top-level performance for the ultra-high-megapixel era

At the dawn of the film camera, there was very little high-sensitivity film, and bright lenses that worked well in low-light conditions came to be known as “high-speed lenses.” These lenses are ideal for shooting indoors, in the evening, under cloudy skies, or in any low-light situation. Since the SIGMA 20mm F1.4 DG HSM | Art provides the benefits of an ultra-wide angle lens with minimal distortion, it is ideal for photographing landscapes, starry skies, and architecture. In addition to capturing wide-angle shots with the whole scene in focus, the photographer can leverage wide-open aperture to take snapshots with the subject in focus and the background blurred with an attractive bokeh effect. Designed for ultra-high-megapixel digital cameras, this high-performance lens delivers outstanding resolution and high-clarity image quality even at wide-open aperture.

Art line delivers high-level artistic expression

SIGMA is organizing all its interchangeable lenses into three product lines: Contemporary, Art, and Sports, each with a distinctive concept. Designed with a focus on sophisticated optical performance and abundant expressive power, our Art line lenses deliver high-level artistic expression. Offering astonishing rendering performance that meets the highest standard, they are perfect for landscapes, portraits, still-lifes, close-ups, and casual snaps. They are made for the kind of photography that unleashes the inner artist. A powerful ally in every genre of photography, SIGMA’s Art line lenses excel both in the studio for formal works and outdoors for impressive shots of architecture, starry skies, and many other scenes.

Metal lens cap available (sold separately)

Matching the high-quality finish of the lens exterior, optionally available metal lens cap LC907-02 will go on sale simultaneously with the lens. Featuring materials identical to those of the lens barrel, this metal lens cap establishes a new level of unity within SIGMA’s new lens lines.

SIGMA USB DOCK makes customization and flexible adjustment possible

High-quality design features SIGMA USB DOCK for SIGMA GLOBAL VISION lenses (optional)

With the optional SIGMA USB DOCK, you can update your lens firmware and adjust the focus position and other settings. Simply connect the lens to the SIGMA USB DOCK and the dock to a computer to use the dedicated SIGMA Optimization Pro software and perform various types of customization and adjustment.

New SIGMA GLOBAL VISION product lines are setting new benchmarks for image quality

High peripheral brightness

In our new product lines, the lens caps and AF/MF switches are newly designed to improve usability. To ensure precise operation, internal parts feature generous use of metal and Thermally Stable Composite (TSC)*, which is highly compatible with metal parts. The lens barrel is engraved with the year of release for instant access to this information.

*TSC offers thermal expansion characteristics similar to those of aluminum. Parts made with TSC deform less, making lens construction of extremely high precision possible. As compared to polycarbonate containing 20% glass, a commonly used material, TSC offers approximately 70% higher elasticity. As compared to polycarbonate containing 30% glass, it offers 25% higher elasticity. (Comparison is between SIGMA-produced components.)

Evaluation with Sigma's own MTF measuring system “A1”

We used to measure lens performance with MTF measuring system using conventional sensors. However, we’ve now developed our own proprietary MTF (modulation transfer function) measuring system (A1) using 46-megapixel Foveon direct image sensors. Even previously undetectable high-frequency details are now within the scope of our quality control inspections. The SIGMA 50mm F1.4 DG HSM will all be checked using this “A1” before they are shipped.

* A1: Aizu1

Made in Japan

All SIGMA’s manufacturing – right down to molds and parts – with a few exceptions, are carried out under a single integrated production system, entirely in Japan. We are now one of the very few manufacturers whose products are solely “made in Japan”. We like to think our products are somehow imbued with the essence of our homeland, blessed as it is with clean air and water, and focused, hard-working people. We pride ourselves on the authentic quality of SIGMA products, born of a marriage between highly attuned expertise and intelligent, advanced technology. Our sophisticated products have satisfied professionals and lovers of photography all over the world, because our manufacturing is based on genuine craftsmanship, underpinned by the passion and pride of our experts.

Incorporating Rounded Diaphragm

The 9 blade-rounded diaphragm creates an attractive blur to the out-of-focus areas of the image.

Hyper Sonic Motor ensures High AF Speed

The HSM (Hyper Sonic Motor) ensures a silent, high-speed AF function. By optimizing the AF algorithm, smoother AF is achieved. It incorporates a new full-time manual focusing mechanism that switches to manual focusing, simply by rotating the focus ring, even when AF is being used. This allows the photographer to make focus adjustments quickly and easily. With the optional SIGMA USB DOCK, you can also set it to conventional full-time manual focus override.

*Depending on the mount, initial operation of full-time manual focus differs

Brass made bayonet mount

This lens incorporates a brass made bayonet mount which has both high accuracy and durability. A special treatment to reinforce its strength is applied to the surface giving it greater strength and making it highly resistant to long-term use.

Applicable for the Mount Conversion Service

As an experienced lens manufacturer that has been creating a diverse range of interchangeable lenses, we have started the innovative chargeable service “Mount Conversion Service”. With this service, the mount of your current SIGMA lenses can be changed to another mount of your choice. It gives a new life to your favorite lenses when you wish to use it on a different camera body.

* This “Mount Conversion Service” is different from a normal repair. In order to apply for the service, please see our Service & Support Section.

Corresponding AF Mounts

SIGMA / NIKON / CANON/ SONY E-Mount (2018)

Nikon mounts do not have an aperture ring. Some functions may not work depending on the camera model.
This lens cannot be used with film SLR cameras with the exception of the Nikon F6 and Canon EOS-1v.
The angle of view varies depending on which camera the lens is mounted on.
Appearance and specifications are subject to change without notice.

The world's first F1.4 ultra-wide-angle lens for full-frame DSLRs

Lens construction



20mm F1.4 DG HSM

Lens Construction 15 elements in 11 groups
Angle of View (for SD1) 94.5 degrees
Number of Diaphragm Blades 9 Blades (Rounded diaphragm)
Minimum Aperture F16
Minimum Focusing Distance 27.6cm / 10.9in.
Maximum Magnification 1:7.1
Dimensions Diameter 90.7mm x Length 129.8mm / 3.6in. x 5.1in
Weight 950g / 33.5oz

The appearance and specifications are subject to change without a notice.

Corresponding AF Mounts

Barcode No.

Sigma 00-85126-412562
Canon 00-85126-412548
Nikon 00-85126-412555
Sony E-Mount 00-85126-412654
L-Mount 00-85126-412969

The world's first F1.4 ultra-wide-angle lens for full-frame DSLRs

Diffraction MTF


Geometrical MTF






The world's first F1.4 ultra-wide-angle lens for full-frame DSLRs

In the news

The Sigma 20mm F1.4 DG HSM is a very fast, tack-sharp prime lens in Sigma’s excellent Art series, and also a unique lens to boot, as it’s the only 20mm lens in the World to offer an f/1.4 aperture. Build quality is excellent, with the brass lens mount and sober all-black design adding to the high-quality feel, and Sigma have even generously included a good fixed lens hood and padded case. Focusing was quick on the Canon EOS 5DS R that we tested the lens with, and manual focus over-ride at any time is a great feature. …we can strongly recommend the new Sigma 20mm F1.4 DG HSM as a very fast, well-built ultra-wide-angle prime lens that delivers excellent image quality.

The lens uses an HSM motor and focusing on the 6D was quiet, positive and without hesitation. The lens locks on every time. Sharpness is impressive. Even at open aperture the centre is already excellent, becoming outstanding from f/2 to f4 and remaining at excellent levels right through to f/16. This is a very high standard in any event, but especially so for such a wide lens. The Sigma 20mm f/1.4 Art Lens is most definitely a fine example of the lens makers’ art. It performs superbly, it focuses close, it is free from flare and controls CA in a remarkable way. The price is high, but its position seems, at least for the moment, to be unique.

Rattling off a series of frames of the same scene from f/1.4 to f/16 and then analysing these alongside our Applied Imaging tests revealed a jaw-dropping set of results. By paying a premium for this lens you get first-class image quality and performance in return. Overall, this is yet another valuable addition to Sigma’s Art line-up of premium lenses and once again highlights Sigma as a brand that’s at the forefront of innovative lens design.

Fitted with a brass mount and constructed of equal parts metal and Thermally Stable Composite, it’s reassuringly hefty for a professional lens. Sigma has once again maintained its excellent form with the 20mm f/1.4 Art. Performing brilliantly even at its maximum aperture, it’s deserving of its professional asking price. If you’re looking for the perfect blend of wide-angle and fast aperture, look no further than this brilliant prime.

The Sigma 20mm f1.4 DG HSM Art is a one-of-a-kind lens: It simply is the widest full-frame f1.4 lens around and it also delivers very good image quality. As such the new Sigma is a very compelling addition to the catalogue of large aperture wide-angle lenses. Add Sigma’s build-quality of the “Art” series and the option to swap the lens-mount should you change your system and you should have a clear winner. …the Sigma 20mm f1.4 DG HSM Art plays on a very high level and as such earns our Highly Recommended rating.

The optical path includes two fluorite-grade FLD elements and no less than five SLD (Special Low Dispersion) elements, aiming to deliver excellent sharpness and contrast, with minimal colour fringing. For such an ultra-wide-angle lens, sharpness is superb across the whole frame. It’s very noticeably better than the Canon 20mm lens in this

With a luxurious matt finish, the lens has a feeling of real quality. Its wide, ribbed focus ring is smooth to operate and autofocus is rapid and accurate. It produces very sharp, crisp images. I wouldn’t like this as my only lens, since the very wide angle limits its applications. However, I’d be delighted to have it as part of my kit and was extremely impressed with the resulting images.

The world's first F1.4 ultra-wide-angle lens for full-frame DSLRs


Cover Lens Cap for 20mm F1.4 DG HSM | Art (LC907-01)

Item No. 4127Z7


Metallic Cover Lens Cap for 20mm F1.4 DG HSM | Art (LC907-02)

The plastic version of the Cover Lens Cap is supplied with the purchase of the 20mm F1.4 DG HSm | Art lens and the Metallic option is sold as a separate accessory item.

Item No. AC47Z1


Padded Case for 20mm F1.4 DG HSM Art

Item No. CS0347


Padded Case for 20mm F1.4 DG HSM Art – Sony E fitting only

Item No. CS0363


Rear Lens Cap

Protect the rear elements of your lens with a SIGMA Rear Lens Cap. Helps to prevent dust, scratches and unwanted damage to the lens contacts. Supplied with new SIGMA Global Vision lenses* *Excluding some lens variants.

Item No.


Sigma USB Dock UD-01

SIGMA USB DOCK enables photographers to update the lens firmware and adjust parameters such as focus. It is designed for use with the New Contemporary, Art and Sports product lines. The adjustment is processed with special software (SIGMA Optimization Pro). The AF speed, focus limiter and OS function are also customizable for Sports lenses. Requires …

Item No.


Sigma USB Dock UD-11

Designed exclusively for the use with a SIGMA Contemporary, Art, or Sports lens and its accessories, the SIGMA USB DOCK allows users to update firmware and customize settings on lenses in these lineups. As the latest addition to the lineup, the USB DOCK UD-11 is designed for two types of mirrorless camera mounts: the L-Mount …

Item No.