Best camera for the canon rf 1200mm f 8l is usm?

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From Canon RF 1200mm f/8L IS USM: Canon RF 1200mm f/8L IS USM: A prime lens by Canon for Full frame cameras, 1200mm f/8. The longest autofocus lens Canon makes. Specs - Maker: Canon - Focal length: 1200mm (prime) - Maximum aperture: f/8 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 1200mm. - On APS-C (Canon) (Canon RF): like 1920mm on full frame; ...

From Portraits: The camera: What matters most is eye autofocus, which current mirrorless cameras do very well: it finds the nearest eye and tracks it, so wide apertures stay sharp. Full frame gives you more background blur at the same f-number than APS-C, but a fast APS-C lens closes most of that gap for far less money; see sensor sizes.

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