Sigma 18 50mm f 2 8 dc dn contemporary vs tamron 16 50mm f 2 8 a?

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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 Tamron 16-50mm f/2.8 A: Tamron 16-50mm f/2.8 A: A zoom lens by Tamron for APS-C cameras, 16-50mm f/2.8. A 305-gram constant f/2.8 standard zoom for APS-C mirrorless bodies. Specs - Maker: Tamron - Focal length: 16-50mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Nikon Z, Fujifilm X, Canon RF - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E, Nikon Z, Fujifilm X): like 24-75mm on ...

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