What are the alternatives to the laowa 4mm f 2 8 fisheye mft?

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From Laowa 4mm f/2.8 Fisheye MFT: Laowa 4mm f/2.8 Fisheye MFT: A prime lens by Laowa for Micro Four Thirds cameras, 4mm f/2.8. A tiny circular fisheye. Specs - Maker: Laowa - Focal length: 4mm (prime) - Maximum aperture: f/2.8 - Made for: Micro Four Thirds sensors - Mounts: Micro Four Thirds - Stabilised: no - Autofocus: no, manual focus What it frames like - On Micro Four Thirds (Micro Four Thirds): like 8mm on full frame; f/2.8 gives about the ...

From 7Artisans 4mm f/2.8 Fisheye: 7Artisans 4mm f/2.8 Fisheye: A prime lens by 7Artisans for APS-C cameras, 4mm f/2.8. A 225-degree circular fisheye.

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