This versatile, full-frame standard prime lens has been designed from the ground up for mirrorless cameras. Its 50mm focal length and ultra-wide F1.4 aperture make it ideal for almost any genre of photography, including portraits, weddings, street, landscapes and travel. Optically the lens delivers exceptional sharpness across the frame, allowing photographers to capture characterful images in remarkable detail, even on the highest resolution mirrorless cameras. Background blur is smooth and attractive – perfect when shooting with a shallow depth-of-field.
The 50mm F1.4 has Sigma’s exceptionally fast, accurate and quiet High-response Liner Actuator (HLA) motor built in, which provides superb AF performance for both stills and video. Included on the lens is a manual aperture ring, which has a useful de-click function for smooth aperture transitions, and a lock function to keep aperture control in either manual or auto. A customisable AFL button is included on the lens, as well as a robust lockable lens hood. Used widely by professional photographers, the lens is also ideal for casual day-to-day shooting, weighing in at just 670g.
The exceptional build quality of the 50mm F1.4 DG DN is exactly as you’d expect from an Art-line lens, in the materials used, the overall ergonomics and the quality of craftsmanship.
The exterior barrel is made of a polycarbonate called Thermally Stable Composite (TSC). Not only is this very strong and light, but it has a similar thermal expansion rate to aluminium. This ensures that the interior aluminium parts and the exterior TSC parts behave in the same way as temperatures change.
The focus ring is rubberised for easier operation, and focusing is internal, meaning the lens never changes length. This makes it ideal for use on a gimbal as the centre of gravity remains fairly constant.
Towards the rear of the barrel is an aperture ring so that aperture can be changed on the lens, and it has an Auto setting should users prefer to change aperture using the camera.
To reduce flare and ghosting in bright sun, and to help protect the front element from damage if dropped, the lens has a robust petal-type lens hood with lock button. A rubberised ring on the hood makes for easier removal and fitting.
The durable brass mount is surrounded by a rubber seal to help keep out dust and moisture.
Precision brass mount with seal
Protects against dust and moisture.
Made from a strong and light polycarbonate that behaves in a similar way to aluminium.
Focus Mode switch
For changing between AF and MF.
Customisable depending on camera body.
Aperture Click switch
Clicks or de-clicks the aperture ring.
A range of controls on the lens include an AF/MF switch, and a customisable AFL button (depending on camera model).
The lens also has a click/de-click switch so that the aperture ring can be adjusted smoothly rather than in hard stops, which may be useful for film-makers. There’s also a lock switch that keeps the aperture ring in either Auto or Manual. This stops the ring accidentally being knocked out of Auto to F16 during use.
The 50mm F1.4 DG DN | Art was only the second SIGMA lens to be fitted with its High-response Linear Actuator (HLA) motor, which controls the focus group of lens elements. More powerful than a stepping motor, it ensures extremely rapid AF. It’s also very accurate and near-silent, and works well with focus tracking systems.
The other advantage the powerful HLA motor brings is that it can move larger and heavier focusing groups than a stepping motor, which unlocks the door more advanced optical designs, and therefore even better optical performance.
The 50mm boasts outstanding optical quality with excellent rendering of detail right into the corners even wide open at F1.4.
Its advanced optical design is made up of 14 elements in 11 groups, including 3 aspherical elements and 1 SLD element. These help to ensure razor-sharp results and eliminate chromatic aberration, flare, distortion and vignetting.
Advanced optical coatings reduce flare and ghosting when working in bright direct sunlight, creating high-contrast images with rich colours and strong blacks.
With an F1.4 aperture, the lens can produce a very shallow depth-of-field, ideal for creating portraits with blurry backgrounds. The bokeh is smooth and attractive.
The 50mm focal length is perfect for the most flattering perspective on the face with a waist-up composition.
The lens is also able to collect four times more light than an F2.8 optic, so if light is low there is much less risk of camera shake and unwanted blur.
SIGMA has two full-frame mirrorless 50mm lenses in its line-up. The 50mm F1.4 DG DN is an Art lens and the 50mm F2 is an I series Contemporary lens. Image quality and build quality are comparable, but the Art lens has a more advanced feature-set, such as an F1.4 aperture, a de-clickable aperture ring, an AFL button and an HLA focusing motor. However, it is almost twice the weight and length so is less portable than the I series option.
All Sigma cameras and lenses are designed, manufactured and assembled at our 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.
Sigma chose Aizu as its main production base in the early 1970s. Situated at the base of Mount Bandai in the Fukushima Prefecture, about four hours’ drive north of Tokyo, Aizu has an abundance of very clean water from mountain streams, which is essential for grinding and polishing lenses. Sigma’s founder, Michihiro Yamaki, was also drawn to this area for its workforce, who have a reputation for their craftsmanship, work ethic and attention to detail. Mr Yamaki’s son, Kazuto Yamaki, now the owner and CEO of SIGMA Corporation, has the same unwavering commitment to keeping production in Japan.
Today Sigma’s factory is more than 50,000 square feet in size, and packed full of some of the most advanced optical manufacturing technology in existence. So when you buy a Sigma camera or lens you can be sure that virtually every single component part has been manufactured and assembled by SIGMA, in Japan, with the greatest level of care and attention. We hope you enjoy using our products.
If you want to see how a particular SIGMA lens or camera performs, why not test drive it with our SIGMA Select hire service. Available for selected SIGMA lenses, short-term loans are free of charge (including shipping), with a small fee if you want to test it for longer. Refundable deposit required. Subject to availability.
14 elements in 11 groups
Angle of view
Number of diaphragm blades
11 (rounded diaphragm)
Minimum focusing distance
Maximum magnification ratio
Dimensions (diameter x length)
ø78.2mm × 109.5mm
Corresponding AF mounts
L-Mount | Sony E
Sony E barcode
Specifications are for L-Mount
A special coating applied to the front element to help repel water and oil.
This suppresses flare and ghosting by minimising reflections within the lens, ensuring punchy, high-contrast results. All lenses in the current Sigma range feature this technology.
Internal focus or an inner focus system means the lens configuration uses movable internal lens elements that adjust focus without changing the length of the lens barrel. This helps keep the centre of gravity of the lens more constant when changing focus.
The lens has an image circle large enough to be used on a full-frame camera. It can also be used on cameras with a smaller ‘crop’ sensor, provided the mount is compatible.
The lens has a filter thread around the front element onto which filters and filter holders can be attached.
The mount is the part of the lens that attaches to the camera body. A coated brass mount is used for strength, and is surrounded by a rubber seal to keep out dust and moisture.
Found on the barrel of some Sigma lenses, the AFL button can be assigned to various functions to widen the range of operations available on the lens (available functions depend on the camera model).
This switch toggles between autofocus and manual focus.
The diaphragm is constructed of 11 rounded blades for a circular aperture opening and round out-of-focus highlights.