Pentax hd fa 35mm f 2 vs pentax hd fa 31mm f 1 8 limited?

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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 Pentax HD FA 35mm f/2: Pentax HD FA 35mm f/2: A prime lens by Pentax for Full frame cameras, 35mm f/2. Specs - Maker: Pentax - Focal length: 35mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On full frame (Pentax K): as marked, 35mm. - On APS-C (Pentax K): like 52mm on full frame; f/2 gives about the depth of field ...

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