Canon ef 200mm f 2 8l ii usm vs sigma 135mm f 1 8 dg hsm art?

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From Canon EF 200mm f/2.8L II USM: Canon EF 200mm f/2.8L II USM: A prime lens by Canon for Full frame cameras, 200mm f/2.8. Specs - Maker: Canon - Focal length: 200mm (prime) - 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, 200mm. - On APS-C (Canon) (Canon EF): like 320mm on full frame; f/2.8 gives about the depth of ...

From Sigma 135mm f/1.8 DG HSM Art: Sigma 135mm f/1.8 DG HSM Art: A prime lens by Sigma for Full frame cameras, 135mm f/1.8. Specs - Maker: Sigma - Focal length: 135mm (prime) - Maximum aperture: f/1.8 - 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, 135mm. - On APS-C (Nikon F, Sony E, ...

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