Canon ef 70 200mm f 2 8l is iii usm vs sigma 70 200mm f 2 8?

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From Canon EF 70-200mm f/2.8L IS III USM: Canon EF 70-200mm f/2.8L IS III USM: A zoom lens by Canon for Full frame cameras, 70-200mm f/2.8. Specs - Maker: Canon - Focal length: 70-200mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 70-200mm. - On APS-C (Canon) (Canon EF): like 112-320mm on full frame; f/2.8 gives about the depth of ...

From Canon EF 70-200mm f/2.8L USM: Canon EF 70-200mm f/2.8L USM: A zoom lens by Canon for Full frame cameras, 70-200mm f/2.8.

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