Sony vario tessar t fe 24 70mm f 4 za oss vs samyang af 24 70mm f 2 8 fe?

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From Sony Vario-Tessar T* FE 24-70mm f/4 ZA OSS: Sony Vario-Tessar T* FE 24-70mm f/4 ZA OSS: A zoom lens by Sony for Full frame cameras, 24-70mm f/4. Specs - Maker: Sony - Focal length: 24-70mm (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, 24-70mm. - On APS-C (Sony E): like 36-105mm on full frame; f/4 gives about the depth of field ...

From Samyang AF 24-70mm f/2.8 FE: Samyang AF 24-70mm f/2.8 FE: A zoom lens by Samyang for Full frame cameras, 24-70mm f/2.8. Specs - Maker: Samyang - Focal length: 24-70mm (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, 24-70mm. - On APS-C (Sony E): like 36-105mm on full frame; f/2.8 gives about the depth of field ...

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