Sigma 20mm f 2 dg contemporary vs zeiss loxia 21mm f 2 8?

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From Sigma 20mm f/2 DG Contemporary: Sigma 20mm f/2 DG Contemporary: A prime lens by Sigma for Full frame cameras, 20mm f/2. A small metal ultra-wide from the I series; sold as the 20mm f/2 DG DN Contemporary before 2025. Specs - Maker: Sigma - Focal length: 20mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E, L-Mount): ...

From Zeiss Loxia 21mm f/2.8: Zeiss Loxia 21mm f/2.8: A prime lens by Zeiss for Full frame cameras, 21mm f/2.8. A small manual-focus wide-angle, popular for landscapes and astro. Specs - Maker: Zeiss - Focal length: 21mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E): as marked, 21mm. - On APS-C (Sony E): like ...

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