Sigma 18 50mm f 2 8 dc dn contemporary vs sony e 18 50mm f 4 5 6?

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From Sigma 18-50mm f/2.8 DC DN Contemporary: Sigma 18-50mm f/2.8 DC DN Contemporary: A zoom lens by Sigma for APS-C cameras, 18-50mm f/2.8. A tiny constant f/2.8 standard zoom: the best upgrade from a kit lens on APS-C. Specs - Maker: Sigma - Focal length: 18-50mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Fujifilm X, L-Mount, Canon RF - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E, Fujifilm X, L-Mount): ...

From Sony E 18-50mm f/4-5.6: Sony E 18-50mm f/4-5.6: A zoom lens by Sony for APS-C cameras, 18-50mm f/4-5.6. Specs - Maker: Sony - Focal length: 18-50mm (zoom) - Maximum aperture: f/4-5.6 (it gets darker as you zoom in) - Made for: APS-C sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E): like 27-75mm on full frame; f/4-5.6 gives about the depth of field of f/6-8.4 there. - ...

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