Part of the I series range of lenses in the Contemporary line-up, this ultra-wide-angle prime for mirrorless cameras is one the of the most compact full-frame wide-angle lenses on the market. Despite this it has a retro-style all-metal construction, including an all-metal petal-type hood, a manual aperture ring and a metal focus ring, giving it a premium and stylish feel.
Image quality is absolutely exceptional across the whole frame, and there is a 55mm thread around the front element for attaching filters. The lens is ideal for landscape, interior, wedding and architectural photography, and in particular for photographers who like to work light, or carry their kit over long distances.
Although the 17mm F4 has a premium all-metal build constructed with precision-cut aluminium parts, the it only weights 225g, making it perfect for outdoor and travel photographers who prefer a compact but robust lens that can easily be carried around all day. A dust- and splash-proof mount is fitted to help stop contamination from dust and water.
The tactile knurled metal lens hood, focus ring and aperture ring improve the grip on the lens for greater control. Included with the lens is a magnetic metal lens cap, which further improves ease of use. The lens features a 55mm filer thread, the same size as the 24mm F3.5 DG DN | C, 45mm F2.8 DG DN | C, and 90mm F2.8 DG DN | C, making it easy to swap filters and reduce overall kit weight.
Metal mount with seal
Protects against dust and moisture.
All-metal aperture ring
Delivers a smooth but precise action. Includes an Auto setting for in-camera control.
Despite its size, the 17mm F4 does not compromise on optical quality. Its advanced optical design includes 9 elements in 8 groups, of which 3 are aspherical elements and 2 are SLD elements. These help to keep the lens compact while greatly reducing the appearance of chromatic aberration around areas of high contrast. Vignetting is very minimal even wide-open, which is important on ultra-wide-angle lenses.
Owing to its advanced Super Multi-Layer lens coatings, the 17mm F4 displays very minimal flare, which makes it ideal for shooting into bright light sources, such as a low sun.
Unusual for an ultra-wide-angle lens, the SIGMA 17mm has a minimum focusing distance of just 12cm, with a minimum working distance (from the subject to the front of the lens) of just over 7cm. This 1:3.6 magnification ratio allows photographers to shoot detailed close-ups without needing a dedicated macro lens.
The 17mm F4 is a superb optic for anyone needing a high performance, ultra-wide-angle lens that is small and light enough to carry around all day. It is exceptionally portable at half the length and half the weight of the SIGMA 16-28mm F2.8 DG DN | C, although it doesn’t have zoom functionality or an F2.8 aperture.
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.
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.
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.
9 elements in 8 groups
Angle of view
Number of diaphragm blades
7 (rounded diaphragm)
Minimum focusing distance
Maximum magnification ratio
Dimensions (diameter x length)
ø64.0mm × 48.8mm
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.
The magnetic lens cap comes boxes with all I series lenses (except the 45mm F2.8), in addition to the standard plastic cap. It attaches to the lens magnetically.
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.
This switch toggles between autofocus and manual focus.
The diaphragm is constructed of nine rounded blades for a circular aperture opening and round out-of-focus highlights.