Sigma 28-105mm f/2.8 DG DN Art Lens for L Mount

The SIGMA 28-105mm F2.8 DG DN | Art lens is a surprisingly compact, full-frame, wide-angle to telephoto zoom lens with a fast constant aperture. Available for Sony E-mount and L-Mount, this lens spans several popular focal lengths from 28mm to 105mm including the very popular 85mm focal length for portraiture, remaining at F2.8 through the entire range.
Featuring HLA (High-response Linear Actuator) autofocus, and optical performance that lives up to the standard of Art line lenses, the SIGMA 28-105mm F2.8 DG DN | Art joins SIGMA's lineup of fast-aperture zoom lenses in the Art line, offering photographers and videographers a variety of premium standard zoom options depending on their personal style. Like the 24-70mm F2.8 DG DN II | Art and the 28-45mm F2.8 DG DN | Art, the new 28-105mm F2.8 includes a lockable aperture ring with click/declick function, as well as two AFL buttons and a zoom lock switch. Additionally, the dust- and splash-resistant design and water-and oil-repellant coating on the front element also makes it suitable for shooting both stills and video in inclement weather.

A minimum focusing distance of 15.8 inches (40cm) at all focal lengths, and maximum magnification ratio of 1:3.1 at the telephoto end add to the versatility of this new zoom lens. This lens also features a rounded twelve-blade diaphragm, which helps to keep the large-aperture unit as small as possible.

Measures have been taken to minimize changes in optical performance due to differences in zoom and focus positions, including the use of a difficult-to-process large-diameter FLD glass in the first group to suppress aberrations in each group. In addition, the use of 5 aspherical lens elements has enabled the lens to achieve both a wide zoom range of 28mm to 105mm and a large-aperture of F2.8, while reducing its overall size.
By thoroughly reducing the weight of each part, the lens is kept under 2 pounds while achieving both a wide zoom range and an F2.8 aperture. The lens barrel near the mount is made of magnesium rather than aluminum, ensuring rigidity while reducing the weight of these parts alone by two-thirds.