Tamron 17-70mm F/2.8 Di III-A VC RXD

A versatile lens with a fast and constant aperture

- Matthew Richards

Overall construction feels sturdy, despite being low in weight. The lens extends at longer zoom settings, from 119mm to 147mm. A fluorine coating is applied to the front to repel moisture.

Mount the Tamron 17-70mm F/2.8 Di III-A VC RXD on an APS-C format Sony E-mount mirrorless body and it will function with an effective zoom range of 25.5-105mm. That’s very similar to using the highly popular Sony FE 24-105mm f/4 G OSS on a full-frame camera, but with the added bonus that the Tamron’s constant aperture rating is a full f-stop faster. Naturally, you get the same effective zoom range with the Fujifilm X-mount version of the lens.

The zoom range and f/2.8 constant aperture are key features of this lens. Sigma used to make something similar for Canon and Nikon APS-C format DSLRs, in the shape of the 17-70mm F2.8-4 Macro OS HSM Contemporary, as well as a non-stabilised version for Sony A and Pentax K mount cameras. Naturally, the Sigma lacked a constant aperture, which shrank from f/2.8 to f/4 at the long end of the zoom range.

Performance

In the Sony E-mount edition that we tested, autofocus proved to be fast and consistently accurate, as well as being fully compatible with advanced AF modes featured in recent cameras. Moreover, we found Vibration Compensation to be worth about 3-4 stops in beating camera shake during handheld shooting.

The lens works well on both focused and out-of-focus shots.