What is the canon ef 100 400mm f 4 5 5 6l is usm good for?

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From Canon EF 100-400mm f/4.5-5.6L IS USM: Canon EF 100-400mm f/4.5-5.6L IS USM: A zoom lens by Canon for Full frame cameras, 100-400mm f/4.5-5.6. The original push-pull version, common on the used market. Specs - Maker: Canon - Focal length: 100-400mm (zoom) - Maximum aperture: f/4.5-5.6 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 100-400mm. - ...

From Canon EF 100-400mm f/4.5-5.6L IS II USM: Canon EF 100-400mm f/4.5-5.6L IS II USM: A zoom lens by Canon for Full frame cameras, 100-400mm f/4.5-5.6.

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