Sigma 50 120mm f 2 8 dc os contemporary vs sony e 18 135mm f 3 5 5 6 oss?

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From Sony E 18-135mm f/3.5-5.6 OSS: Sony E 18-135mm f/3.5-5.6 OSS: A zoom lens by Sony for APS-C cameras, 18-135mm f/3.5-5.6. A good travel zoom for the APS-C bodies. Specs - Maker: Sony - Focal length: 18-135mm (zoom) - Maximum aperture: f/3.5-5.6 (it gets darker as you zoom in) - Made for: APS-C sensors - Mounts: Sony E - Stabilised: yes - Autofocus: yes What it frames like - On APS-C (Sony E): like 27-202mm on full frame; f/3.5-5.6 gives about ...

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 ...

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