Pentax hd fa 31mm f 1 8 limited vs sigma 35mm f 1 4 dg hsm art?

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From Pentax HD FA 31mm f/1.8 Limited: Pentax HD FA 31mm f/1.8 Limited: A prime lens by Pentax for Full frame cameras, 31mm f/1.8. Same optics as the earlier smc FA 31mm Limited. Specs - Maker: Pentax - Focal length: 31mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On full frame (Pentax K): as marked, 31mm. - On APS-C (Pentax K): like 46mm on ...

From Sigma 35mm f/1.4 DG HSM Art: Sigma 35mm f/1.4 DG HSM Art: A prime lens by Sigma for Full frame cameras, 35mm f/1.4. The 2012 lens that started Sigma's Art line; common and cheap used. Specs - Maker: Sigma - Focal length: 35mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Canon EF, Nikon F, Pentax K, Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon ...

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