Sigma has announced the ultra-compact, wide aperture 20mm F2 DG DN I Contemporary wide-angle lens that’s for E-mount and L-Mount systems.

It’s a full-frame compact prime optic for mirrorless cameras and is the seventh lens in Sigma’s fast-growing I series lens line-up, following the 90mm f2.8 DG DN. It’s also the widest angle lens in the range so far, so can open up fresh photographic possibilities for I series users.

The fact that the lens is available for both E-Mount and L-Mount systems means it is compatible with Sony, Leica, Panasonic LUMIX and Sigma cameras, including the E-Mount Sony Alpha A7 IV,  and L-Mount Panasonic Lumix S5, and Sigma fp L to name a few.

The lens weighs 370g and measures 72.4mm in length (L-Mount version), making it an easily  portable optic. The 20mm focal length can be used for landscapes, wide-angle portraits, weddings and interiors.

The latest Sigma prime is also said to be ‘particularly well-suited to astrophotography owing to its very well-controlled sagittal coma flare.’

The lens has a UK SRP of £649.99 and will go on sale from 25 February 2022.

The new 20mm Sigma optic shown with lens hood

The new 20mm Sigma optic shown with lens hood

Press release from Sigma (dated 9 February 2022)

I series | Premium Compact Primes for mirrorless users

New standards of optical performance for the Contemporary line

Exceptional I series build quality with a compact form-factor

UK SRP: £649.99 On sale date: 25 February 2022

Introducing the all-new 20mm F2 DG DN | Contemporary from SIGMA. This ultra-compact, wide-aperture prime lens for E-mount and L-Mount systems is a game changer for mirrorless users needing a sharp, wide-angle optic that isn’t going to weight them down.

This portable, full-frame premium compact prime for mirrorless cameras is the seventh lens in SIGMA’s fast-growing I series lineup, combining a bright maximum aperture of F2, an ultra-wide 20mm focal length and stunning optical performance. It’s also the widest lens in the range so far, opening up new photographic possibilities for I series users.

A side view of the Sigma 20mm F2 DG DN lens with the AF/MF switch shown

A side view of the Sigma 20mm F2 DG DN lens with the AF/MF switch shown

The lens boasts an exceptionally small form factor, weighing in at 370g and measuring just 72.4mm in length*, which makes it a highly practical optic that is portable enough for everyday shooting. It’s ideal for landscapes, wide-angle portraits, weddings and interiors, and is particularly well-suited to astrophotography owing to its very well-controlled sagittal coma flare. It’s the fourth I series lens with an F2 aperture, joining a 24mm, 35mm and 65mm, which together make a well-matched lens set for photographers who need both performance and portability in their kitbag. Remarkably, the 20mm F2 DG DN | Contemporary is almost identical in size and weight to the SIGMA 24mm F2 I series. Its sleek, all metal design, with a signature I series magnetic lens cap, a manual aperture ring and exceptional build quality makes using this lens is a highly intuitive and satisfying experience.

*Figures are for L-Mount

Key features

I series | ‘Premium Compact Primes’ for mirrorless users

The SIGMA I series features full-frame compatible lenses that offer new value to mirrorless systems. The combination of superb optical performance with a level of compactness that is perfectly suited to modern mirrorless cameras offer up new opportunities for a perfect shot. SIGMA is aware that in today’s world we have a wide range of camera choices, especially with the increase in mobile phone ownership. But with many photographers looking for something more than something that simply captures images when they choose to own a camera and lens, I series lenses offer the ultimate combination of superb optical performance, outstanding usability and compact form-factor. SIGMA’s excellence in development and production technologies has been built up since our founding in 1961 and became increasingly sophisticated with the introduction of the SIGMA Global Vision brand in 2012. With this as a base, SIGMA has given careful thought to the quality of a product, the feeling of using it and the pleasure of owning it. This is how the I series was born.

New standards of optical performance for the contemporary line

The 20mm F2 DG DN | Contemporary achieves the highest level of optical performance even wide open, from the centre of the image to the periphery. Based on the latest optical design technology, the lens construction includes three high-precision glass-molded aspherical lens elements, one SLD element, and one FLD element to suppress a range of optical aberrations. The result is clear and sharp images even in the extreme corners of the frame. By focusing on the suppression of sagittal coma flare, which is difficult to correct in post-processing, accurate reproduction of very bright points of light has been achieved. This provides extremely detailed results across the entire image, which is especially important for night sky photography.

The lens’ advanced optical design, as well as its Super Multi-Layer Coating and Nano Porous Coating (NPC), ensures very minimal flare and ghosting even when shooting into bright light sources. This makes it much easier to photograph backlit subjects and still achieve punchy, high contrast results.


Exceptional I series build quality with a compact form-factor

All I series lenses have an all-metal construction. The precision-cut aluminium parts not only give the barrel a sleek, stylish finish, but provide superb durability that improves the quality of the entire product. Metal materials are also used in internal structures that slide with the operation ring for added robustness. These high-precision components crafted with SIGMA’s cutting-edge metalworking technology are also used in SIGMA’s CINE LENS line-up for professional cinematographers and provide a tactile, ergonomic feel that make the lens a pleasure to use.

The cover ring between the focus ring and the aperture ring has hairline processing that is also used for the rear cylinder of the Art line. This covering functions as a finger hold when attaching or detaching the lens.

Additional features

  • Lens construction: 13 elements in 11 groups, with 1 FLD, 1 SLD and 3 aspherical elements
  • Inner focus system
  • Compatible with high-speed autofocus
  • Stepping Motor
  • Compatible with Lens Aberration Correction (*function available on supported cameras only. Available corrections may vary depending on the camera model)
  • Support DMF and AF+MF
  • Nano Porous Coating
  • Super Multi-Layer Coating
  • Aperture ring
  • Focus Mode Switch
  • Petal-type lens hood (LH656-03)
  • Magnetic metal lens cap (LCF62-01M)
  • Mount with dust and splash resistant structure
  • Support for switching between linear and non-linear focus ring settings (for L-Mount only)
  • Compatible with SIGMA USB DOCK UD-11 (sold separately / for L-Mount only)
  • Designed to minimise flare and ghosting
  • Every single lens undergoes SIGMA’s proprietary MTF measuring system
  • 9-blade rounded diaphragm
  • High-precision, durable brass bayonet mount
  • ‘Made in Japan’ craftsmanship

Key specifications (The figures below are for L-Mount)

Lens construction: 11 groups, 13 elements (1 FLD, 1 SLD and 3 aspherical elements)

Angle of view: 94.5°
Number of diaphragm blades: 9 (rounded diaphragm)
Minimum aperture: F22

Minimum focusing distance: 22cm
Maximum magnification ratio: 1:6.7
Filter size: 62mm
Dimensions (max diameter x length): 70mmx72.4mm

Weight: 370g


L-Mount: 0085126 490690 | Sony E-mount: 0085126 490652

Supplied accessories


Optional accessories

SIGMA USB DOCK UD-11 for L-Mount





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Sigma 18-50mm F2.8 DC DN | C review – a fine fast zoom for APS-C

Sigma 90mm F2.8 DG DN I Contemporary review

Sigma 24mm F2 DG DN I Contemporary review

Sigma 35mm F1.4 DG DN Art Review

Sigma fp L review