According to CanonRumors, Canon is working on a new 50mm prime lens (no mention of aperture), to replace current EF 50mm f/1.4 USM or EF 50mm f/1.2L USM lens.
We are also told Canon is working on a new image stabilized 50mm lens. Because IS version 50mm prime lens will add size and cost, it is not likely to see a 50mm f/1.4 or f/1.2L IS lens, mostly it will be a EF-M 50mm IS lens.
via: CR
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