Canon Apparently Has a Focal Reducer for EF-M Mount in the Works

Canon is developing a Metabones-inspired focal reducer for the EOS M system that will convert a 50mm f1.4 lens to a 40mm f1.2–or at least that’s what a patent says!

Despite the EOS R full-frame mirrorless camera being the most popular of Canon’s recent releases, the company has maintained its commitment to the EOS M APS-C mirrorless camera line. Looks like they’re busy cooking up something to prove this as well; reports have surfaced about a Canon patent for a Metabones-inspired speed booster for the EF-M mount.

Canon Rumors and Digital Camera World reported on the Japan Patent Application 2018-189864 recently filed by Canon for a converter that takes EF lenses to reduce the focal length and the decrease the aperture. The application demonstrated an example where a 50mm f1.4 full frame lens with a back focus of 39.80 (EF full frame) gets converted to a 40mm f1.2 lens with an image height of 13.66 and an 18mm back focus. The report also mentions that this would work on EOS M mount cameras.

A Metabones focal length reducer

For those hearing about the term for the first time, a speed booster (also called a focal reducer or telecompressor) is a converter that reduces the aperture and focal length of an attached lens. Therefore, it does the opposite of a teleconverter and increases the lens speed, hence the term “speed booster.”

To make things more interesting, Canon News has also found that in an earlier Japan Patent Application 2018-185393, Canon referenced the US patent by Caldwell Photographic, the company that manufactures the Metabones brand of speed boosters. While there is currently no Metabones speed booster for the EF-M mount, Viltrox has recently released one (EM-F to EF). Still, the idea of an official focal reducer by Canon, especially if the company is indeed dedicated to keep the EOS M line going, is an interesting and appealing one for many Canon photographers.

Let’s see how this pans out!


Image via Japan Platform for Patent Information