Sigma 15mm f 1 4 dg dn diagonal fisheye art vs viltrox af 16mm f 1 8?

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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 Viltrox AF 16mm f/1.8: Viltrox AF 16mm f/1.8: A prime lens by Viltrox for Full frame cameras, 16mm f/1.8. Specs - Maker: Viltrox - Focal length: 16mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Sony E, Nikon Z, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E, Nikon Z, L-Mount): as marked, 16mm. - On APS-C (Sony E, Nikon Z, L-Mount): like 24mm on ...

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