Is the canon rf 5 2mm f 2 8l dual fisheye hard to focus manually?

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From Canon RF 5.2mm f/2.8L Dual Fisheye: Canon RF 5.2mm f/2.8L Dual Fisheye: A prime lens by Canon for Full frame cameras, 5.2mm f/2.8. A twin-lens 3D VR lens for full-frame bodies, manual focus only. Specs - Maker: Canon - Focal length: 5.2mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Canon RF): as marked, 5.2mm. - On APS-C (Canon) ...

From Buying used: Checking a camera body: - Shutter count. Shutters wear out eventually. Ask for the count, or read it from a test photo's metadata with an online tool where the brand supports it, and compare with the rated life for that model. - The sensor. Take a photo of a plain sky at f/16 and look for dark spots (dust is fixable; scratches are not). - Ports, buttons and dials. Try every button, the card ...

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