Pentax smc da 18 270mm f 3 5 6 3 ed sdm vs pentax 55 300mm f 4 5 8?

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From Pentax smc DA 18-270mm f/3.5-6.3 ED SDM: Pentax smc DA 18-270mm f/3.5-6.3 ED SDM: A zoom lens by Pentax for APS-C cameras, 18-270mm f/3.5-6.3. Specs - Maker: Pentax - Focal length: 18-270mm (zoom) - Maximum aperture: f/3.5-6.3 (it gets darker as you zoom in) - Made for: APS-C sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Pentax K): like 27-405mm on full frame; f/3.5-6.3 gives about the depth of field of f/5.2-9.4 there. - ...

From [Pentax smc DA* 300mm f/4 ED [IF] SDM: Pentax smc DA* 300mm f/4 ED [IF] SDM](/gear/lenses/pentax-smc-da-300mm-f-4-ed-if-sdm/): A prime lens by Pentax for APS-C cameras, 300mm f/4. A weather-sealed telephoto prime for wildlife.

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