17mm F4
DG DN

The lens construction consists of two SLD glass elements and three aspherical lens elements. Aspherical lenses are used for both the front and rear optics. This not only keeps the size of the lens compact but also helps with correcting lens aberrations. As a result, the lens features a φ55mm filter thread (which is smaller than comparable lenses of similar focal lengths) which makes it easy to change filters between Sigma I series lenses that share the same filter size. * Its construction also helps minimize flare and ghosting that is commonly found in ultra-wide-angle lenses, creating clear images in any environment. This is a lens with truly modern performance, thanks to the advanced processing and production technologies at Sigma’s only production facility in Aizu.
A highlight of using the 17mm is the impressive minimum focusing distance of 12cm. Capture close-up macro style images in remarkable detail with expansive backgrounds. It is also suitable for selfies and vlogging, where items need to be shown at an arms-reach. A quiet, high-speed stepping motor drives the AF delivering fast and accurate results in both stills and video.

*In addition to the 17mm F4 DG DN | Contemporary, I series lenses with a φ55mm filter thread include the 24mm F3.5 DG DN | Contemporary, 45mm F2.8 DG DN | Contemporary, and 90mm F2.8 DG DN | Contemporary (as of April 2023).

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 people look for something more than a mere act of “taking pictures” when they choose to own a camera and lenses, 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 the products, the feeling of using it and the pleasure of owning it. This is how the I series was born.

I series - The Stage is Set.
Uncompromising optical performance, pure quality and operability that gives you the pleasure of owning it ーall combined in the compact lens body. The SIGMA I series is a set of full-frame compatible lenses that offer new value to mirrorless systems.

SIGMA breaks the new ground with a wide range of focal lengths.
The Stage is Set.

The cold, bold texture of the metal. The weight that feels just right. The ring with an addictive touch and operation. The clicking sound that you want to move and hear over and over again.
The deep sense of satisfaction that makes your heart skip a beat just by its presence by your side.
The SIGMA I series has been developed with the aim of fulfilling desires that could not be satisfied with lenses ever before.

The special movie depicts daily life with the I series and the small but important joys that come with it.

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 line-up for professional cinematographers and provide a tactile, ergonomic feel that make the lens a pleasure to use. What is more with the I series is that this high build quality is condensed into a palm-sized lens body. The Sigma 17mm F4 DG DN | Contemporary is one of the smallest in the series. Combine with multiple I series lenses to create a remarkably compact shooting system that is lightweight and small in size.

※ The image is 35mm
※ Cannot be used when a filter is attached.

I series lenses are accompanied by a dedicated magnetic metal lens cap*, in addition to a normal plastic cap. This dedicated metal cap clips to the front surface of the lens magnetically. It is no exaggeration to say that this meticulously crafted cap represents the finishing touch for the I series.

*Except Sigma 45mm F2.8 DG DN | Contemporary

When a cap is removed from the lens it should have a proper place where it can be kept. Using this as a starting point, a cap holder using the magnetic force of the dedicated cap was created.
With the cap attached to the ring plate, and the plate clipped to a bag or belt, the cap is always within easy reach and is less likely to get lost. Plus, its elegant design is a stylish addition to a photographer’s equipment.