Sigma has announced the 28-70mm F2.8 DG DN zoom lens.
The Sigma 28-70mm F2.8 DG DN Contemporary lens is a standard zoom lens for mirrorless cameras that combines optical performance based on the popular Art series with a constant F2.8 aperture.
Part of the Contemporary line, which is considered Sigma's more budget-friendly series, the new lens follows in the footsteps of the 24-70mm F2.8 DG OS HSM Art lens. The 4mm difference in focal length makes the lens a bit more compact and about half the weight (470g to 835g).
Optically, it's constructed from 16 elements in 12 groups, with two FLD elements, two SLD elements, and three aspherical elements. Sigma says that despite having fewer elements than the Art version, it still thoroughly corrects axial chromatic aberration and sagittal coma aberration. The lens also has multiple coatings to reduce flares, control contrast, and anti-ghosting. On top of that, it features water- and oil-repellent coatings for added reassurance out in the field. It has a 9 blade aperture.
The lens supports autofocus, as it has a single stepping motor to keep the AF unit small and quiet. When adjusting the focal length, the lens will change in physical length, so keep that in mind when using follow focus systems. On the barrel, Sigma added a focus mode switch, but it does lack the AFL button or zoom lock switch found on the Art model.
For close work, the lens has a 7.4" (19cm) minimum focusing distance on the wide end and 14.9" (38cm) minimum focusing distance on the long end. It supports 67mm filters.
The Sigma 28-70mm F2.8 DG DN Contemporary is available in L-mount and Sony E mount for $899 with an expected March release date. That's $200 cheaper than the 24-70mm F2.8 DG DN Art.