Sigma’s premium primes ‘I’ perfection

Freshly engineered for mirrorless, here come 24mm f/2 and 90mm f/2.8 'I Series' primes for Sony, Sigma, Leica and Panasonic bodies

Sigma has launched two new prime lenses into its ‘I Series’ range, all lenses in which are designed from the ground up for full-frame mirrorless systems. The 24mm f/2 DG DN Contemporary and 90mm f/2.8 DG DN Contemporary will come in fits for Sony E-mount cameras as well as the L-mount shared by Sigma, Leica and Panasonic bodies. 

The 24mm f/2 DG DN Contemporary is designed for photographers who need a wide-angle optic that’s sharp, fast, robust and light. Its combination of a large, 84.1° field-of-view and an f/2 maximum aperture means it should be of interest to all sorts of photographers, including those shooting documentary, street, travel and even night-skies, where Sigma says sagittal coma flare is well suppressed for clear pin-points of light.

It has a construction of 13 elements in 11 groups, including two glass-molded aspherical elements, one FLD and two SLD elements. These elements are treated to Sigma’s Super Multi-layer coating to reduce flare, ghosting and other aberrations. It has a nine-blade rounded diaphragm, too. An internally focusing lens, the minimum distance is 24.5cm at which it has a magnification ratio of 1:6.7, and for AF it uses a stepping motor for faster, quieter focusing. It’ll take 62mm filters. 

© Aya Iwasaki

The 90mm f/2.8 DG DN is a versatile mid-telephoto lens, with an angle of view of 27° and other features that should make it attractive to portrait, nature and still-life photographers. It uses a construction of 11 elements in 10 groups, this time featuring one glass-molded aspherical element and five SLD elements, and again using Sigma’s Super Multi-Layer Coating to resist flare and ghosting. A nine-bladed, rounded aperture diaphragm promises large, circular bokeh for smoother background blur. 

The minimum focus distance is 50cm, producing a magnification ratio of 1:5, so detailed closeups should be highly achievable, and with an internal focusing design, the front element won’t shift as the lens locks on. Its AF system uses a high-speed stepping motor, a bonus of which is that it should be quiet enough for video applications as well as stills, and the 90mm f/2.8 DG DN will take 55mm filters.

© Aya Iwasaki

Like all of Sigma’s I Series lenses, these new models have an all-metal barrel design made from precision-cut aluminium, a durable brass bayonet mount, weather sealing and feature a physical aperture ring. Both also come with a metal lens hood, as well as regular and magnetic lens caps. 

Both lenses are small and light, too, being designed for mobility and to balance with smaller mirrorless bodies. The 24mm f/2 DG DN measures 70x74mm and weighs 365g in E-mount and 70x72mm and 360g in L-mount. The 90mm f/2.8 DG DN measures 64x62mm in E-mount and 64x60mm in L-mount, but weighs 295g in both. The two new lenses are available now, each with an SRP of £549.99.