Patent: RF/EF 400mm f/4 DO, 600mm f/4 DO, 800mm f/5.6 DO Lenses
Canon recently has filed a new lens patent in Japan. This patent is for 400mm f/4 DO lens, 600mm f/4 DO lens, and 800mm f/5.6 lens. The patent didn’t mention whether this lens is EF mount or RF mount, but hi-lows-note said these lenses could be RF mount, and upcoming EOS R could have IBIS.