Panasonic lumix s 20 60mm f 3 5 5 6 vs sigma 20 60mm f 2 8 4 dg contemporary?

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From Panasonic Lumix S 20-60mm f/3.5-5.6: Panasonic Lumix S 20-60mm f/3.5-5.6: A zoom lens by Panasonic for Full frame cameras, 20-60mm f/3.5-5.6. A kit zoom that starts at a genuinely wide 20mm. Specs - Maker: Panasonic - Focal length: 20-60mm (zoom) - Maximum aperture: f/3.5-5.6 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (L-Mount): as marked, 20-60mm. - On ...

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 ...

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