Fast. Sharp. Versatile. Portable.
Designed for crop sensor mirrorless cameras, the 23mm has an equivalent focal length of 37mm, making it a versatile wide-standard prime that is well suited to street photography, landscapes, wider-angle portraits, weddings and travel. Its F1.4 aperture ensures fast shutter speeds for working hand-held in low-light conditions, and also provides a very shallow depth-of-field for blurry backgrounds.

Despite its very fast aperture the lens weighs only 345g, so it’s easily light enough to carry around all day, and the build is sleek yet robust. Optical performance is exceptional, with very sharp results across the whole frame at all aperture settings. The lens pairs perfectly with the other DC DN primes, which also have F1.4 apertures.

Features and build
As with the other optics in Sigma’s F1.4 DC DN range, the 23mm F1.4 is constructed with a strong and light polymer that ensures a strong build while keeping the lens portable. A large, rubberised focus ring makes manual focusing highly intuitive, and a petal-type lens hood helps control flare in bright sunlight.

The durable brass mount is surrounded by a rubber seal to help keep out dust and moisture. The lens benefits from inner focusing technology, with a stepping motor that delivers smooth, fast and accurate AF for both stills and video. It has been designed with lighter glass elements in the focus lens group, which ensures responsive autofocus that is fully compatible with all the latest AF camera technology.

High-performance optics
Despite weighing only 345g, the 23mm F1.4 DC DN | C delivers outstanding optical quality across the whole frame, even on high-resolution sensors. Its advanced optical design is made up of 13 elements in 10 groups, including 2 aspherical elements and 3 SLD elements. These ensure razor-sharp results and help to eliminate common optical issues such as chromatic aberration, flare and vignetting. The lens also utilises in-camera digital correction to fine-tune the final result.

Important for a wide-angle lens, optical performance is maintained across the whole frame, meaning fine detail is captured perfectly right into the corners. Chromatic aberration is very well-controlled around areas of high contrast, and vignetting is minimal even wide-open. The lens has advanced optical coatings which reduce flare and ghosting when working in bright direct sunlight – important on a wide-angle lens.

Excellent low-light performance
The lens has a very bright maximum aperture of F1.4 that allows plenty of light through the lens. For astrophotographers, this ensures lots of sky detail in shorter exposures, and for photographers using the lens hand-held in low-light conditions, such as at night, it helps eliminate camera-shake.

A fast aperture also means a shallow depth-of-field for blurry backgrounds. This allows photographers to isolate their subject and create more impactful images. The bokeh is smooth and attractive, so doesn’t distract from the in-focus subject.

Compact and lightweight
The 23mm F1.4 and the 18-50mm F2.8 are both excellent options for photographers who need a standard crop sensor lens that is both sharp and portable. The 23mm is slightly heavier and longer and doesn’t have zoom functionality, although it does have a faster aperture of F1.4, which lets in four times as much light and creates a shallower depth-of-field.