Leaked images and specifications point to a compact, stabilised 50-120mm f/2.8 telephoto zoom for APS-C mirrorless cameras from Sigma, weighing just 390g.

Sigma looks set to add a fast telephoto zoom to its APS-C line-up, after images and specifications of a new 50-120mm f/2.8 DC OS | Contemporary lens appeared online. The leak was first published by Sony Alpha Rumors, which credits the images and specs to the leaker How2Fly.

Sigma has not officially announced the lens, so everything below should be treated as unconfirmed until it does.

According to the leaked specifications, the lens uses 18 elements in 13 groups and features optical stabilisation, rated at 6.5 stops at the wide end and 4.5 stops at the telephoto end. Autofocus is driven by Sigma’s HLA linear motor.

Close focusing looks strong for a telephoto zoom, with a minimum focus distance of 23cm at 50mm and 55cm at 120mm, giving maximum magnifications of 1:3 and 1:4.7 respectively. The lens reportedly takes 55mm filters and weighs 390g in Sony E-mount form.

Our take

On an APS-C body, 50-120mm gives a full-frame equivalent of roughly 75-180mm, which makes this a natural partner to Sigma’s popular 17-40mm f/1.8 and 18-50mm f/2.8 zooms. A constant f/2.8 telephoto at under 400g, with stabilisation built in, would be a strong option for portraits, events and wildlife on smaller bodies like the Sony a6700 and Fujifilm X-S20. Sony Alpha Rumors had previously suggested an announcement date of 8 October, so we may not have long to wait for confirmation.

Sigma 50-120mm f/2.8 DC OS | Contemporary leaked specifications

Sigma 50-120mm f/2.8 DC OS | Contemporary price and availability

Sigma has yet to announce the lens, and there’s no word on price or which mounts will be offered beyond Sony E. We’ll update this story when Sigma makes it official. You can read the original report on Sony Alpha Rumors.