Canon ef 135mm f 2l usm vs sigma 105mm f 1 4 dg hsm art?

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From Sigma 105mm f/1.4 DG HSM Art: Sigma 105mm f/1.4 DG HSM Art: A prime lens by Sigma for Full frame cameras, 105mm f/1.4. A very large, very heavy portrait prime known for its background blur. Specs - Maker: Sigma - Focal length: 105mm (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 ...

From Canon EF 135mm f/2L USM: Canon EF 135mm f/2L USM: A prime lens by Canon for Full frame cameras, 135mm f/2. Specs - Maker: Canon - Focal length: 135mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 135mm. - On APS-C (Canon) (Canon EF): like 216mm on full frame; f/2 gives about the depth of ...

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