Sources say Canon will release RF 400mm f / 4 DO IS USM shots next year.

CTOnews.com, November 16 (Xinhua)-- A niche but popular lens in the EF bayonet era is expected to adopt a new design for RF processing in 2024, the Canon RF 400mm f / 4 DO IS USM.

Canon will release the RF 400mm f / 4 DO IS USM telefocus lens next year, which may adopt a new optical design, CanonRumors said.

Canon has previously launched three "DO" brand lenses, all of which are suitable for EF bayonets. The first was the EF 400mm f / 4 DO IS USM launched in 2001, followed by the more affordable zoom model EF 70-300mm f / 4.5-5.6DO IS USM in 2004.

In 2014, Canon released the EF 400mm f / 4 DO IS USM II, which improved the contrast issues found in the first version. However, CTOnews.com inquiry found that all EF DO-branded lenses that Canon has launched so far have been discontinued.

Many years ago, Canon showed off a prototype of the EF 600mm f / 4 DO IS USM that has never been on the market, and according to CanonRumors, Canon is developing a 600mm f / 4 DO lens, which will be released later than the RF 400mm f / 4 DO IS USM.