Pentax hd fa 77mm f 1 8 limited vs pentax smc da 50mm f 1 8?

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From Pentax HD FA 77mm f/1.8 Limited: Pentax HD FA 77mm f/1.8 Limited: A prime lens by Pentax for Full frame cameras, 77mm f/1.8. Same optics as the earlier smc FA 77mm Limited. Specs - Maker: Pentax - Focal length: 77mm (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, 77mm. - On APS-C (Pentax K): like 116mm on ...

From Pentax smc DA 50mm f/1.8: Pentax smc DA 50mm f/1.8: A prime lens by Pentax for APS-C cameras, 50mm f/1.8. The cheapest fast portrait lens for Pentax APS-C bodies. Specs - Maker: Pentax - Focal length: 50mm (prime) - Maximum aperture: f/1.8 - Made for: APS-C sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Pentax K): like 75mm on full frame; f/1.8 gives about the depth of field of f/2.7 ...

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