Sigma 28mm f 1 4 dg hsm art vs canon ef 28mm f 1 8 usm?

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From Sigma 28mm f/1.4 DG HSM Art: Sigma 28mm f/1.4 DG HSM Art: A prime lens by Sigma for Full frame cameras, 28mm f/1.4. Specs - Maker: Sigma - Focal length: 28mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Canon EF, Nikon F, Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon F, Sony E, L-Mount): as marked, 28mm. - On APS-C (Nikon F, Sony E, ...

From Canon EF 28mm f/1.8 USM: Canon EF 28mm f/1.8 USM: A prime lens by Canon for Full frame cameras, 28mm f/1.8. Specs - Maker: Canon - Focal length: 28mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 28mm. - On APS-C (Canon) (Canon EF): like 45mm on full frame; f/1.8 gives about the depth of ...

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