Sony e 20mm f 2 8 vs 7artisans af 18mm f 2?

Here is what the site says about that.

From Sony E 20mm f/2.8: Sony E 20mm f/2.8: A prime lens by Sony for APS-C cameras, 20mm f/2.8. Specs - Maker: Sony - Focal length: 20mm (prime) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E): like 30mm on full frame; f/2.8 gives about the depth of field of f/4.2 there. - On the larger-sensor bodies of Sony E: ...

From 7Artisans AF 18mm f/2: 7Artisans AF 18mm f/2: A prime lens by 7Artisans for APS-C cameras, 18mm f/2. Specs - Maker: 7Artisans - Focal length: 18mm (prime) - Maximum aperture: f/2 - Made for: APS-C sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E): like 27mm on full frame; f/2 gives about the depth of field of f/3 there. - On the larger-sensor bodies of Sony E: ...

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