This all-new full-frame premium compact prime for mirrorless systems is the latest addition to SIGMA's I series lineup, combining a bright maximum aperture of F2, an ultra-wide 20mm focal length and stunning optical performance. The lens boasts an exceptionally small form factor, weighing in at just 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 is the fourth I series lens with an F2 aperture, joining a 24mm, 35mm and 65mm, which together make a well-matched lens set for L-Mount and Sony E-mount 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 smaller and lighter modern mirrorless cameras will bring you 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 formfactor.
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 the products, the feeling of using it and the pleasure of owning it. This is how the I series was born.
The 20mm F2 DG DN | Contemporary achieves the highest level of optical performance even at the widest aperture setting of F2 from the center 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 also provides extremely detailed results across the entire image, especially important for night sky photography.
The lens' 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.
All I series lenses have an all-metal construction. The precision-cut aluminum 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 lineup 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.
Minimum Aperture | F22 |
Focus Type | Autofocus | Manual Focus |
Lens Filter Size | 62 mm (Front) |
Angle of View (diagonal) | 94.5° |
Lens Min. Focus Distance | 22cm / 8.7 in. |
Maximum Aperture | F/2.0 |
Mount Type | Leica L Mount |
Focal Length | 20mm |
Weight | 370g / 13.1 oz. |
Dimensions | 70 x 72.4mm / 2.8 x 2.9 in |
Image Stabilization | No |
Diaphragm Blades | 9 (rounded diaphragm) |
Optical Design | 11 groups, 13 elements (1 FLD, 1 SLD, 3 aspherical) |
Brand | Sigma |