Canon EF 400mm F5.6L IS USM lens will be coming soon! According to latest rumors from CR2, Canon currently is working on a new super telephoto lens that is slower than f/4.
Canon released the current EF 400mm F5.6L USM lens several years ago and this new IS lens will be announced in 2016.
Apparently, Sigma and Tamron both released their super telephoto zoom lenses: Sigma 150-600mm f/5-6.3 and Tamron 150-600mm f/5-6.3 with an affordable price.
Source: CR2
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