Tamron is bringing its 17-70mm f/2.8 Di III-A VC RXD APS-C zoom lens to Canon RF- and Nikon Z-mount mirrorless cameras.

The lens was initially released for Sony E-mount cameras back in late 2020, and was the world’s first APS-C zoom lens to feature a 4.1 times zoom ratio and constant f/2.8 aperture.

On Nikon’s APS-C cameras, which feature a 1.5 times crop factor, the Tamron 17-70mm f/2.8 Di III-A VC RXD delivers a 25.5-105mm equivalent focal length range. Meanwhile, on Canon’s APS-C mirrorless cameras, which have a slightly longer 1.6 times crop, it is a 27.2-112mm equivalent zoom lens. In both cases, the lens promises to be very versatile, working well for travel, landscapes, and even portraits thanks to its fast aperture and mid-telephoto reach.

On both Canon and Nikon’s mirrorless systems, Tamron’s 17-70mm f/2.8 lens brings something unique to the table. While Nikon did bring some new APS-C lenses into the fold last year, including an impressive Nikkor Z DX 16-50mm f/2.8 VR zoom, Tamron’s zoom delivers even more reach with the same f/2.8 aperture.

On Canon’s side, the company’s RF-S (APS-C) lenses are much slower zooms, with non-constant apertures ranging from f/4.5-6.3 and f/3.5-6.3 IS STM. Tamron’s lens addresses a real need here, which is a significant reason why Canon opened up its RF mount system to third-party autofocus lenses, but only APS-C ones. It allows Canon to focus more of its efforts on developing new full-frame lenses while ensuring that its APS-C users have ample choice. There’s little doubt photographers would enjoy the same openness for full-frame lenses, but alas.

Aside from the new mounts, there are minimal changes made to the Tamron 17-70mm f/2.8 lens. The Nikon Z-mount version, like other Tamron lenses for Z-mount, ditches the dedicated AF/MF and VC ON/OFF barrel switch, delegating these controls to the attached camera’s menu system. Otherwise, the lenses are identical to their E-mount predecessor.

The 17-70mm f/2.8 includes 16 elements arranged across a dozen groups, a nine-bladed circular aperture diaphragm, and Tamron’s preferred 67mm front filter thread.

The RF-mount version weighs 530 grams (18.7 ounces), while the Z lens is 540 grams (19 ounces). They are both around 120 millimeters (4.7 inches) long, although the RF version is ever so slightly shorter. The lens features a moisture-resistant construction and a fluorine coating on the front element.

The Tamron 17-70mm f/2.8 promises reasonable, albeit not macro-level, close-up performance. The lens can focus as close as 0.19 meters (7.5 inches) at the wide end and 0.39 meters (15.4 inches) at tele. The maximum magnification ratios are 1:4.8 and 1:5.2, respectively.

Pricing and Availability

The Tamron 17-70mm f/2.8 Di III-A VC RXD (Model B070) officially arrives for Canon RF- and Nikon Z-mount on July 2 for $749 ($949 in Canada). This is $50 more than the list price for the E-mount version, which is actually even cheaper right now thanks to a $100 discount. It is currently $599.

Image credits: Tamron