Sigma 50 120mm f 2 8 dc os contemporary vs tamron 70 180mm f 2 8 di iii vxd?

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From Sigma 50-120mm f/2.8 DC OS Contemporary: Sigma 50-120mm f/2.8 DC OS Contemporary: A zoom lens by Sigma for APS-C cameras, 50-120mm f/2.8. A compact constant f/2.8 telephoto zoom for APS-C, about 75-180mm equivalent. Specs - Maker: Sigma - Focal length: 50-120mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Fujifilm X, Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On APS-C (Sony E, Fujifilm X): like 75-180mm on full frame; f/2.8 ...

From Tamron 70-180mm f/2.8 Di III VXD: Tamron 70-180mm f/2.8 Di III VXD: A zoom lens by Tamron for Full frame cameras, 70-180mm f/2.8. The first-generation version, without stabilisation; discontinued but common used. Specs - Maker: Tamron - Focal length: 70-180mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 70-180mm. - On APS-C (Sony E): like 105-270mm on ...

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