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Leica apo summicron sl 35mm f 2 asph vs sigma 35mm f 2 dg contemporary?

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From Leica APO-Summicron-SL 35mm f/2 ASPH: Leica APO-Summicron-SL 35mm f/2 ASPH: A prime lens by Leica for Full frame cameras, 35mm f/2. Specs - Maker: Leica - Focal length: 35mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (L-Mount): as marked, 35mm. - On APS-C (L-Mount): like 52mm on full frame; f/2 gives about the depth of field of f/3 there. ...

From Sigma 35mm f/2 DG Contemporary: Sigma 35mm f/2 DG Contemporary: A prime lens by Sigma for Full frame cameras, 35mm f/2. Specs - Maker: Sigma - Focal length: 35mm (prime) - Maximum aperture: f/2 - 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, 35mm. - On APS-C (Sony E, L-Mount): like 52mm on full frame; f/2 gives about the ...

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