Sigma's $799 50-120mm f/2.8 Gives APS-C Shooters a 75-180mm-Equivalent Telephoto Zoom

Sigma has announced the The 50-120mm f/2.8 DC OS Contemporary, a stabilized telephoto zoom for APS-C mirrorless cameras that covers roughly 75-180mm in full frame terms at a constant f/2.8 and goes on sale October 22 for $799 in Sony E, Fujifilm X, and Canon RF mounts.

The lens completes Sigma's set of constant f/2.8 Contemporary zooms for APS-C, joining the Sigma 10-18mm f/2.8 DC DN Contemporary and the Sigma 18-50mm f/2.8 DC DN Contemporary. Together, the three cover roughly 15-180mm equivalent and weigh less than 2.2 lb (1 kg), according to Sigma. The 50-120mm is also the first APS-C zoom in the Contemporary line with an aperture ring. Sigma positions it as the APS-C stand-in for a 70-200mm f/2.8, at 13.8 oz (390 g) and 3.9 inches (99mm) long in its Sony E version.

Stabilization Rated Up to 6.5 Stops

Sigma's OS2 stabilization algorithm is rated for 6.5 stops of correction at 50mm and 4.5 stops at 120mm, based on CIPA guidelines and measured on an APS-C mirrorless camera. Sigma pitches it for handholding at slower shutter speeds in low light and for steadier handheld video, including on bodies without in-body stabilization.

Autofocus and Video

An HLA (High-response Linear Actuator) motor drives the focus group, which Sigma describes as fast and quiet. The optical design minimizes focus breathing, so framing stays steadier as focus shifts between subjects. Sigma says the aperture ring is meant for hands-on exposure control in stills and smooth iris changes in video.

Optics

The lens uses 18 elements in 13 groups, including one FLD element, three SLD elements, and four aspherical elements. An 11-blade rounded diaphragm stops down to f/22. Minimum focus distance is 9.1 inches (23 cm) at 50mm and 21.7 inches (55 cm) at 120mm, for a maximum magnification of 1:3 at the wide end and 1:4.7 at the long end.

Build and Mount Differences

The lens is built to resist dust and splashes, and its front element carries a coating that repels water and oil. Sigma notes that the lens is not waterproof and warns against heavy splashing near water. It takes 55mm filters and comes out of Sigma's own factory in Aizu, Japan, where the company designs, builds, and tests all of its lenses.

The Sony E and Fujifilm X versions both weigh 13.8 oz (390 g) and measure 66.8mm across, at 99.0mm and 99.3mm long, respectively. The Canon RF version is 14.5 oz (410 g), 69.0mm across, and 97.0mm long. Each ships with a pouch, an LH585-01 lens hood, an LCF-55 IV front cap, and an LCR III rear cap.

Key Specs

• Focal length: 50-120mm (approx. 75-180mm full frame equivalent)
• Maximum aperture: f/2.8, constant
• Minimum aperture: f/22
• Optical construction: 18 elements in 13 groups (1 FLD, 3 SLD, 4 aspherical)
• Aperture blades: 11, rounded
• Minimum focus distance: 9.1 inches (23 cm) at 50mm, 21.7 inches (55 cm) at 120mm
• Maximum magnification: 1:3 at 50mm, 1:4.7 at 120mm
• Stabilization: OS2, rated 6.5 stops at 50mm and 4.5 stops at 120mm (CIPA)
• Autofocus motor: HLA (High-response Linear Actuator)
• Controls: manual aperture ring
• Weather resistance: dust- and splash-resistant structure, water- and oil-repellent front coating
• Filter size: 55mm
• Dimensions: 66.8 x 99.0mm (Sony E), 66.8 x 99.3mm (Fujifilm X), 69.0 x 97.0mm (Canon RF)
• Weight: 13.8 oz (390 g) for Sony E and Fujifilm X, 14.5 oz (410 g) for Canon RF
• Mounts: Sony E, Fujifilm X, Canon RF
• Included: pouch, LH585-01 lens hood, LCF-55 IV front cap, LCR III rear cap

Who It's For

If you shoot APS-C on Sony E, Fujifilm X, or Canon RF and want a telephoto zoom for portraits, weddings, events, or indoor sports, the constant f/2.8 and 390 g weight put a 75-180mm-equivalent view on a small body without the bulk of a full frame 70-200mm. The stabilization does the most for you if your camera lacks in-body stabilization, and the minimal focus breathing and aperture ring suit video work. At the same framing, though, f/2.8 on APS-C gives you about the depth of field of f/4 on full frame, so wide-open background blur won't match a full frame 70-200mm f/2.8, even though you still get the f/2.8 exposure in a dim room. If you need more reach for wildlife or field sports, 180mm equivalent runs short, and if you shoot Nikon Z or L-mount, this launch doesn't include your mount.

Price and Availability

The Sigma 50-120mm f/2.8 DC OS Contemporary is available for preorder for $799 in Sony E, Fujifilm X, and Canon RF mounts.