Sigma 20mm f 1 4 dg hsm art vs nikon af s 20mm f 1 8g ed?

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From Nikon AF-S 20mm f/1.8G ED: Nikon AF-S 20mm f/1.8G ED: A prime lens by Nikon for Full frame cameras, 20mm f/1.8. Specs - Maker: Nikon - Focal length: 20mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Nikon F - Stabilised: no - Autofocus: yes What it frames like - On full frame (Nikon F): as marked, 20mm. - On APS-C (Nikon F): like 30mm on full frame; f/1.8 gives about the depth of field ...

From Sigma 20mm f/1.4 DG HSM Art: Sigma 20mm f/1.4 DG HSM Art: A prime lens by Sigma for Full frame cameras, 20mm f/1.4. Specs - Maker: Sigma - Focal length: 20mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Canon EF, Nikon F, Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon F, Sony E, L-Mount): as marked, 20mm. - On APS-C (Nikon F, Sony E, ...

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