What is the canon ef 50mm f 1 4 usm good for?

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From Canon EF 50mm f/1.4 USM: Canon EF 50mm f/1.4 USM: A prime lens by Canon for Full frame cameras, 50mm f/1.4. Specs - Maker: Canon - Focal length: 50mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 50mm. - On APS-C (Canon) (Canon EF): like 80mm on full frame; f/1.4 gives about the depth of ...

From Canon EF 50mm f/1.2L USM: Canon EF 50mm f/1.2L USM: A prime lens by Canon for Full frame cameras, 50mm f/1.2.

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