Looking for a 9.8mm f/2? Or maybe a 11.9mm f/2.8 or 16.8mm f/2.5?
The Metabones SpeedBooster reduces focal length from full frame to APS-C, and increases f-stop by one stop (a natural result by definition of f-stop). So a 14mm lens (full frame) becomes 9.8mm on APS-C with the same field of view on both. Format equivalence.
The Canon 14/2.8L II, 17/4L TS-E, 24/3.5L II are the lenses that produce the stated focal lengths above, using the SpeedBooster.
I’ll be reporting on various Canon lenses as used with the Metabones SpeedBooster on the Sony A6000 later this month. See existing Metabones SpeedBooster coverage.