Several years ago, Canon released the EF 400mm F5.6L USM lens. According to the recent CR, a new IS version replacement will be coming soon. It is Canon EF 400mm F5.6L IS USM lens.
This new super-telephoto prime lens is designed for birders with the lower weight and price. We will see it next year. It seems that Canon will replace all of the 400mm lenses: EF 400mm f/2.8L IS II, EF 400mm f/4 DO IS II, EF 100-400mm f/4.5-5.6L IS II and EF 400mm F5.6L IS USM lens.
Source: CR
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