Canon ef 16 35mm f 2 8l ii usm vs sigma 24 35mm f 2 dg hsm art?

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From Canon EF 16-35mm f/2.8L II USM: Canon EF 16-35mm f/2.8L II USM: A zoom lens by Canon for Full frame cameras, 16-35mm f/2.8. Specs - Maker: Canon - Focal length: 16-35mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 16-35mm. - On APS-C (Canon) (Canon EF): like 26-56mm on full frame; f/2.8 gives about the depth of ...

From Sigma 24-35mm f/2 DG HSM Art: Sigma 24-35mm f/2 DG HSM Art: A zoom lens by Sigma for Full frame cameras, 24-35mm f/2. Specs - Maker: Sigma - Focal length: 24-35mm (zoom) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Canon EF, Nikon F - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon F): as marked, 24-35mm. - On APS-C (Nikon F): like 36-52mm on full frame; f/2 gives about ...

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