Sony vario tessar t fe 16 35mm f 4 za oss vs tamron 17 50mm f 4 di iii vxd?

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From Sony Vario-Tessar T* FE 16-35mm f/4 ZA OSS: Sony Vario-Tessar T* FE 16-35mm f/4 ZA OSS: A zoom lens by Sony for Full frame cameras, 16-35mm f/4. Specs - Maker: Sony - Focal length: 16-35mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 16-35mm. - On APS-C (Sony E): like 24-52mm on full frame; f/4 gives about the depth of field ...

From Tamron 17-50mm f/4 Di III VXD: Tamron 17-50mm f/4 Di III VXD: A zoom lens by Tamron for Full frame cameras, 17-50mm f/4. A light constant f/4 standard zoom that starts at 17mm. Specs - Maker: Tamron - Focal length: 17-50mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 17-50mm. - On APS-C (Sony E): like 26-75mm ...

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