Canon rf 100 300mm f 2 8l is usm vs canon rf 75 300mm f 4 5 6?

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From Canon RF 100-300mm f/2.8L IS USM: Canon RF 100-300mm f/2.8L IS USM: A zoom lens by Canon for Full frame cameras, 100-300mm f/2.8. A professional sport and wildlife zoom that stays at f/2.8 throughout. Specs - Maker: Canon - Focal length: 100-300mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 100-300mm. - On APS-C (Canon) (Canon RF): ...

From Canon RF 75-300mm f/4-5.6: Canon RF 75-300mm f/4-5.6: A zoom lens by Canon for Full frame cameras, 75-300mm f/4-5.6. A cheap, light telephoto zoom, but with no optical stabilisation. Specs - Maker: Canon - Focal length: 75-300mm (zoom) - Maximum aperture: f/4-5.6 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 75-300mm. ...

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