Sigma 20 60mm f 2 8 4 dg contemporary vs sony fe 20 70mm f 4 g?

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From Sigma 20-60mm f/2.8-4 DG Contemporary: Sigma 20-60mm f/2.8-4 DG Contemporary: A zoom lens by Sigma for Full frame cameras, 20-60mm f/2.8-4. A standard zoom that starts at a true ultra-wide 20mm. Specs - Maker: Sigma - Focal length: 20-60mm (zoom) - Maximum aperture: f/2.8-4 (it gets darker as you zoom in) - 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 ...

From Sony FE 20-70mm f/4 G: Sony FE 20-70mm f/4 G: A zoom lens by Sony for Full frame cameras, 20-70mm f/4. Specs - Maker: Sony - Focal length: 20-70mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 20-70mm. - On APS-C (Sony E): like 30-105mm on full frame; f/4 gives about the depth of field ...

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