Sigma 14 24mm f 2 8 dg hsm art vs canon ef 11 24mm f 4l usm?

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From Sigma 14-24mm f/2.8 DG HSM Art: Sigma 14-24mm f/2.8 DG HSM Art: A zoom lens by Sigma for Full frame cameras, 14-24mm f/2.8. Specs - Maker: Sigma - Focal length: 14-24mm (zoom) - Maximum aperture: f/2.8 - 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, 14-24mm. - On APS-C (Nikon F): like 21-36mm on full frame; f/2.8 gives about ...

From Canon EF 11-24mm f/4L USM: Canon EF 11-24mm f/4L USM: A zoom lens by Canon for Full frame cameras, 11-24mm f/4. Specs - Maker: Canon - Focal length: 11-24mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 11-24mm. - On APS-C (Canon) (Canon EF): like 18-38mm on full frame; f/4 gives about the depth of ...

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