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What are the alternatives to the sony e 20mm f 2 8?

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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 Tamron 20mm f/2.8 Di III OSD M1:2: What it frames like: - On full frame (Sony E): as marked, 20mm. - On APS-C (Sony E): like 30mm on full frame; f/2.8 gives about the depth of field of f/4.2 there.

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