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Tamron announced that its 11-20mm f/2.8 Di III-A RXD will be available for Canon RF mount in December. Tamron initially said this lens was coming to RF mount back in April.
Its first RF-mount lens, the 11-20mm f/2.8, is already available for Sony E-mount and Fujifilm X-mount but will be making its debut on Canon RF-mount on December 12. Like with Sigma, Canon has only issued an official license to Tamron to bring over APS-C lenses to its mirrorless platform. While probably frustrating for Canon full-frame photographers, it’s a boon for users of the smaller sensor since Canon’s first-party APS-C lens offerings have been pretty poor and limited.
As a recap, Tamron characterizes the 11-20mm f/2.8 Di III-A RXD as a fast-aperture zoom lens covering a focal length range from ultra-wide-angle 11mm to 20mm that pairs well with a fast f/2.8 aperture through that range. It’s a small and lightweight lens, too, despite the fast aperture and Tamron says it is designed to feel well-balanced when attached to an APS-C mirrorless camera body.
It features a construction of 12 elements arranged into 10 groups, including two GM (Glass Molded Aspherical) lens elements that Tamron says maintain high resolution across the entire image area as well as one XLD (eXtra Low Dispersion) and two LD (Low Dispersion) lens elements that are designed to suppress aberrations.
It uses Tamron’s RXD (Rapid-eXtra-silent stepping Drive) stepping motor unit to drive the autofocus and Tamron says it’s “remarkably quiet” and also fast and smooth enough to make the lens suitable for both photo and video applications.
One notable difference between this RF-mount version and the Sony and Fujifilm versions is that Tamron added a Manual Focus/Autofocus selector switch to the outside of the lens body. The previous design required toggling this from the menu, but Canon’s version offers this physical, tactile switch instead — what is likely seen to be a major upgrade. It also maintains the connection port that allows the lens to be updated using the company’s Lens Utility software.
As mentioned, the Tamron 11-20mm f/2.8 Di III-A RXD will be available on December 12 but, unexpectedly, it will retail for less than the Sony and Fujifilm versions: $659 versus $699.