Pentax smc fa 50mm f 1 4 vs pentax hd fa 43mm f 1 9 limited?

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From Pentax HD FA 43mm f/1.9 Limited: Pentax HD FA 43mm f/1.9 Limited: A prime lens by Pentax for Full frame cameras, 43mm f/1.9. Same optics as the earlier smc FA 43mm Limited. Specs - Maker: Pentax - Focal length: 43mm (prime) - Maximum aperture: f/1.9 - Made for: Full frame sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On full frame (Pentax K): as marked, 43mm. - On APS-C (Pentax K): like 64mm on ...

From Pentax smc FA 50mm f/1.4: Pentax smc FA 50mm f/1.4: A prime lens by Pentax for Full frame cameras, 50mm f/1.4. Specs - Maker: Pentax - Focal length: 50mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On full frame (Pentax K): as marked, 50mm. - On APS-C (Pentax K): like 75mm on full frame; f/1.4 gives about the depth of field ...

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