Sigma 15mm f 1 4 dg dn diagonal fisheye art vs sony fe 14mm f 1 8 gm?

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From Sigma 15mm f/1.4 DG DN Diagonal Fisheye Art: Sigma 15mm f/1.4 DG DN Diagonal Fisheye Art: A prime lens by Sigma for Full frame cameras, 15mm f/1.4. A fast full-frame fisheye, made with night-sky photography in mind. Specs - Maker: Sigma - Focal length: 15mm (prime) - Maximum aperture: f/1.4 - 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): as marked, 15mm. - On APS-C (Sony E, ...

From Sony FE 14mm f/1.8 GM: Sony FE 14mm f/1.8 GM: A prime lens by Sony for Full frame cameras, 14mm f/1.8. Specs - Maker: Sony - Focal length: 14mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 14mm. - On APS-C (Sony E): like 21mm on full frame; f/1.8 gives about the depth of field ...

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