Sigma AF 20mm F2 DG I C lens for L-Mount, Black 

The 20mm F2 DG DN is a full-frame premium compact prime from Sigma’s I series range.

The lens is essentially for photographers and film-makers who value the experience of taking a picture just as much as the quality of the final result.

Designed specifically for mirrorless cameras, it features an ultra-wide-angle focal length that is ideal for landscapes, weddings, interiors and astro.

• Full-Frame
• Internal Focus
• Front Filter Thread
• Brass Mount
• AF MF Switch
• 9 Rounded Blades
• Water and Oil Repellent
• Super Multi-Layer Coating
• Magnetic Lens Cap

Owing to its advanced optical design, which includes three glass-moulded aspherical elements, one SLD element, one FLD element, and nano-porous coatings, the lens delivers exceptional image quality across the frame with very minimal chromatic aberration and well-controlled coma flare.

As with Sigma’s other I series lenses, the 20mm F2 combines superb optical performance with outstanding build quality and retro styling. Its sleek, all-metal body includes a metal focus ring, a metal aperture ring, a metal lens hood, and even a metal lens cap that attaches to the lens magnetically.

Weighing less than 400g, the 20mm F2 is portable enough to be carried around for casual day-to-day shooting, but thanks to its outstanding optics, wide F2 aperture, fast AF and impressive build, is equally well-suited to heavy professional use.

Outstanding Build Quality

Despite having a premium all-metal build comprising precision-cut aluminium parts, the 20mm F2 weighs only 370g (L-Mount), making it perfect for landscape and travel photographers who prefer a compact but robust lens that can easily be carried around all day. The lens has a dust- and splash-proof mount and an aperture ring.

The tactile knurled metal finish used for the lens hood, focus ring and aperture ring make controlling settings and gripping the lens a joy to use. Included with the lens is a magnetic metal lens cap in addition to the regular plastic cap, which further improves ease of use. Unlike some ultra-wide-angle optics, the lens features a 62mm filer thread that makes it easy to attach ND filters, ND grad filters and polarisers, ideal for landscape photography.

• Metal mount with seal: Protects against dust and moisture.
• All-metal construction: Including metal aperture and focus rings.
• Petal-shaped hood: All-metal with individually machine knurled grooves.
• Ultra-compact body: Weighs only 370g, ideal for landscapes and travel.

High-Performance Optics

Despite its size, the 20mm F2 DG DN delivers outstanding optical quality across the whole frame, even on ultra-high-resolution sensors. Owing to its advanced optical design, which includes 13 elements in 11 groups, results remain pin-sharp, even when shooting at the widest aperture of F2. Important for a wide-angle lens, optical performance is maintained across the whole frame, meaning fine detail is perfectly captured right into the corners.

Chromatic aberration is very well-controlled around areas of high contrast, and vignetting is minimal even wide-open. The lens has advanced optical coatings which reduce flare and ghosting when working in bright direct sunlight.

Excellent Low-Light Performance

A bright F2 aperture allows plenty of light through the lens, which is particularly useful in low-light shooting situations. For astrophotographers, it ensures excellent star detail in shorter exposures, and for photographers using the lens hand-held in low-light its helps eliminate camera-shake.

A fast aperture also means a shallow depth-of-field for blurry backgrounds. This allows photographers to isolate their subject and create more impactful images.

Magnetic Lens Cap Holder

Available as a separate accessory, Sigma’s innovative magnetic lens cap holder can be clipped to clothing or a bag to securely hold any I series magnetic lens cap. This helps keep the cap safe while the camera is in use.

Sigma I Series Range

The lens is part of the I series range of primes, which sit in the Contemporary line-up. They are designed to offer mirrorless photographers outstanding optical quality and premium usability in a compact package.

With similar optical character and the same sleek external design, the lenses are ideally used as a set, ensuring consistent bokeh, colour rendition, optical precision and usability.

Made in Japan

All Sigma cameras and lenses are designed, manufactured and assembled at their sole factory at Aizu in Japan. This domestic production model is unusual in today’s industry, with most imaging companies opting to outsource to other countries to reduce costs. But SIGMA believes that keeping virtually all manufacturing, processing and assembly in Aizu is essential for creating innovative, carefully thought-out and impeccably constructed products that meet the high standards demanded by professional photographers and film-makers around the world.