Zeiss loxia 25mm f 2 4 vs zeiss loxia 21mm f 2 8?

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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 ...

From Zeiss Loxia 25mm f/2.4: Zeiss Loxia 25mm f/2.4: A prime lens by Zeiss for Full frame cameras, 25mm f/2.4. Specs - Maker: Zeiss - Focal length: 25mm (prime) - Maximum aperture: f/2.4 - 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, 25mm. - On APS-C (Sony E): like 38mm on full frame; f/2.4 gives about the depth ...

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