The SIGMA I series introduces compact, beautifully designed, high-performance optics for mirrorless camera systems. This 20mm ultra-wide-angle prime with its bright F2 aperture is exceptionally small and light for this type of lens, and is a superb option for landscape, night sky, interior and event photographers who need uncompromising optical quality, excellent portability and fast aperture performance.
Sitting within the contemporary line-up, the 20mm F2 DG DN is available for L-Mount and Sony E-mount cameras, and comes with an all-metal barrel, metal lens hood, magnetic lens cap and manual aperture ring. It is perfectly balanced on a mirrorless body, and unlike SIGMA’s 20mm F1.4 DG HSM | Art comes with a filter thread for added convenience.
New standards of optical quality in 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 optical quality for capturing ultra-sharp night sky images
Astrophotographers require lenses of the very highest quality, as all parts of the frame must be extremely sharp at the widest apertures and flare must be very well controlled. The 20mm F2 DG DN | Art is an exceptionally capable astro lens, partly because of its extremely sharp results across the frame, and partly because it controls sagittal coma flare so effectively, where bright points of light, such as stars, can have a tendency to flare out near to the edges of the frame. Even wide open at F2, coma flare is very minimal right into the corners of the frame.
Compact and sharp: a perfect landscape lens
The lens’ ultra-wide 94.5° angle-of-view makes it a perfect choice for landscape photography. Outstanding optical performance right across the frame ensures sharp corners at all apertures. The advanced lens coatings ensure high-contrast results with vivid colours, which yields punchy and impactful images. A filter thread is included around the front element for easier filter use in the field.
Beautiful bokeh for wide-angle portraits
The 20mm is a very useful lens for weddings, events and environmental portraits, especially when working in tight spaces. The wide F2 aperture ensures fast shutter speeds, making it easier to shoot hand-held in low light, and it also gives a shallow depth-of-field for blurry backgrounds. The bokeh is smooth and attractive with circular highlights. Image: Jim Koepnick
A new experience 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.
Exceptional I series build quality in an ultra-compact body
Sigma is now one of the very few imaging manufacturers whose products are solely made in Japan. This gives us full control over our production processes and helps us maintain the highest levels of quality control over the design, manufacture and construction of every product. Great care is taken to ensure the highest quality materials are chosen.
All I series lenses are designed with an all-metal barrel. The precision-cut aluminium parts not only give the lens a sleek, stylish finish but provide superb durability, which 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 the production of the cine lens line-up for professional film-makers.
The lens has an aperture ring so that users can change aperture using either the lens or the camera. Great attention was paid to ensure the click is well-define but not too sharp. Sound-deadening grease has been used to create a more rounded sound. Similarly the metal focus ring is perfectly weighted for a precise and smooth action to ensure accurate manual focus control.
Remarkably, the 20mm F2 DG DN | C is almost identical in size and weight to the 24mm F2 DG DN | C, despite having a considerably wider angle-of-view (see image). The two lenses join other F2 optics in the I series range, such as the 35mm and 65mm, to make a perfect primes set.
Magnetic metal lens cap and metal lens hood
The 20mm F2 DG DN | C comes with a carefully machined metal lens hood, a feature not even found on Sigma’s Art series lenses. A large number of grooves called ‘knurling’ are cut in, improving the lens operation by serving as slip resistance and giving the lens a premium look and feel unique to the I Series. A specially chosen plastic was used for the part that connects to the lens to ensure smooth operation.
Included in the box is the regular Sigma plastic lens cap as well as an all-metal magnetic cap (pictured left), which snaps firmly on to the end of the lens. With no requirement for a spring-loaded clasp, the cap has a sleek, minimal finish.