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Laowa 15mm f 2 zero d vs sigma 15mm f 1 4 dg dn diagonal fisheye art?

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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 Laowa 15mm f/2 Zero-D: Laowa 15mm f/2 Zero-D: A prime lens by Laowa for Full frame cameras, 15mm f/2. A fast ultra-wide for astro; the Leica M version is sold as the LM. Specs - Maker: Laowa - Focal length: 15mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Sony E, Nikon Z, Canon RF, Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame ...

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