Is the olympus 15mm f 8 body cap lens hard to focus manually?

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From Olympus 15mm f/8 Body Cap Lens: Olympus 15mm f/8 Body Cap Lens: A prime lens by Olympus for Micro Four Thirds cameras, 15mm f/8. A lens as thin as a body cap, with a fixed f/8 aperture and a manual focus lever. Specs - Maker: Olympus - Focal length: 15mm (prime) - Maximum aperture: f/8 - Made for: Micro Four Thirds sensors - Mounts: Micro Four Thirds - Stabilised: no - Autofocus: no, manual focus What it frames like - On Micro ...

From Olympus 9mm f/8 Fisheye Body Cap Lens: Olympus 9mm f/8 Fisheye Body Cap Lens: A prime lens by Olympus for Micro Four Thirds cameras, 9mm f/8. A fisheye as thin as a body cap, with a fixed f/8 aperture and manual focus.

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