What is the pentax smc da 55mm f 1 4 sdm good for?

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From Pentax smc DA* 55mm f/1.4 SDM: Pentax smc DA* 55mm f/1.4 SDM: A prime lens by Pentax for APS-C cameras, 55mm f/1.4. Specs - Maker: Pentax - Focal length: 55mm (prime) - Maximum aperture: f/1.4 - Made for: APS-C sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Pentax K): like 82mm on full frame; f/1.4 gives about the depth of field of f/2.1 there. - On the larger-sensor bodies of Pentax K: ...

From [Pentax smc DA* 60-250mm f/4 ED [IF] SDM: Pentax smc DA* 60-250mm f/4 ED [IF] SDM](/gear/lenses/pentax-smc-da-60-250mm-f-4-ed-if-sdm/): A zoom lens by Pentax for APS-C cameras, 60-250mm f/4.

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