7artisans 4mm f 2 8 fisheye vs 7artisans 6mm f 2?

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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. Specs - Maker: 7Artisans - Focal length: 4mm (prime) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Fujifilm X, Micro Four Thirds - Stabilised: no - Autofocus: no, manual focus What it frames like - On APS-C (Sony E, Fujifilm X): like 6mm on full frame; f/2.8 gives about the depth ...

From 7Artisans 6mm f/2: 7Artisans 6mm f/2: A prime lens by 7Artisans for APS-C cameras, 6mm f/2. Specs - Maker: 7Artisans - Focal length: 6mm (prime) - Maximum aperture: f/2 - Made for: APS-C sensors - Mounts: Sony E, Fujifilm X, Nikon Z, Canon RF, Micro Four Thirds - Stabilised: no - Autofocus: no, manual focus What it frames like - On APS-C (Sony E, Fujifilm X, Nikon Z): like 9mm on full frame; f/2 gives about ...

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