With a focal length of 20mm and F1.4 aperture, this lens delivers outstanding large-aperture brightness and bokeh, delivering unprecedented visual experiences.
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.
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.
Minimized chromatic aberrations
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.
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.
Exclusive low-dispersion glass
The degree to which light is refracted by glass depends on the light's wavelength. This fact causes different colors of light to focus at slightly different points. The result is chromatic aberration, the color fringing that is particularly noticeable in telephoto lenses. Most chromatic aberration can be removed by combining a high-refractivity convex lens element with a low-refractivity concave element. Yet residual chromatic aberration known as “secondary spectrum” may still remain. To minimize this secondary spectrum, which can be a serious issue with conventional lenses, SIGMA lenses feature up to three types of exclusive low-dispersion glass offering superior performance: ELD (Extraordinary Low Dispersion), SLD (Special Low Dispersion) and FLD (“F” Low Dispersion). In particular, FLD glass offers ultra-low dispersion in combination with high transmittance and the anomalous dispersion characteristics of fluorite. Meticulous deployment of these types of exclusive low-dispersion glass and optimization of power distribution gives SIGMA lenses superlative image rendition undiminished by residual chromatic aberration.
Flare and ghosting reduction
From an early stage in the lens design process, flare and ghosting have been measured to establish an optical design resistant to strong incident light sources such as backlighting. SIGMA’s Super Multi-Layer Coating reduces flare and ghosting to help photographers produce sharp and high contrast images even in backlit conditions.SIGMA lens technology
Hyper Sonic Motor ensures high AF speed
The Hyper Sonic Motor (HSM) ensures silent, high-speed autofocusing, while the optimized AF algorithm helps realize even smoother AF performance. At any time during AF, users may access MF simply by rotating the focus ring. This feature makes faster focus adjustment possible, since there is no need to use the AF/MF focus mode switch. Also, the optional SIGMA USB DOCK allows the user to set the lens to conventional full-time manual focus override.
Note: The operation of full-time MF may vary based on mount type.
The 9-blade rounded diaphragm creates an attractive blur in the out-of-focus areas of the image.
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.
High-precision, rugged brass bayonet mount
The brass mount combines high precision with rugged construction. Its treated surfaces and enhanced strength contribute to the exceptional durability of the lens.
46-megapixel Foveon direct image sensor
The 46 effective megapixel (4,800 × 3,200 × 3 layers) and 44 recording megapixel (4,704 × 3,136 × 3 layers) 23.5 × 15.7mm APS-C X3 direct image sensor captures all primary RGB colors at each and every pixel location, ensuring the capture of full and complete color. Using three silicon-embedded layers of photo detectors, stacked vertically to take advantage of silicon's ability to absorb red, green and blue light at different respective depths, it efficiently reproduces color more accurately, and offers sharper resolution, pixel for pixel, than any conventional image sensor. Since color moiré is not generated, the use of a low-pass filter is not required, meaning light and color, generated by the 46-megapixel APS-C X3 direct image sensor is captured with a three-dimensional feel.More about the sensor
MTF chartMTF chart guide
Ultra-high precision and quality—all made in Japan.
With only a few minor exceptions, all of SIGMA's manufacturing, including molds and parts, takes place under a single integrated production system in Japan. We are now one of the very few manufacturers whose products are truly 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.