Nikon z 20mm f 1 8 s vs ttartisan 21mm f 1 5 asph?

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From Nikon Z 20mm f/1.8 S: Nikon Z 20mm f/1.8 S: A prime lens by Nikon for Full frame cameras, 20mm f/1.8. A fast wide prime, popular for landscapes and night skies. Specs - Maker: Nikon - Focal length: 20mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Nikon Z - Stabilised: no - Autofocus: yes What it frames like - On full frame (Nikon Z): as marked, 20mm. - On APS-C (Nikon Z): like 30mm ...

From TTArtisan 21mm f/1.5 ASPH: TTArtisan 21mm f/1.5 ASPH: A prime lens by TTArtisan for Full frame cameras, 21mm f/1.5. Specs - Maker: TTArtisan - Focal length: 21mm (prime) - Maximum aperture: f/1.5 - Made for: Full frame sensors - Mounts: Sony E, Nikon Z, Canon RF, Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E, Nikon Z, Canon RF, Leica M): as marked, 21mm. - On APS-C ...

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