Sigma 18 35mm f 1 8 dc hsm art vs pentax smc da 16 45mm f 4 ed al?

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From Pentax smc DA 16-45mm f/4 ED AL: Pentax smc DA 16-45mm f/4 ED AL: A zoom lens by Pentax for APS-C cameras, 16-45mm f/4. Specs - Maker: Pentax - Focal length: 16-45mm (zoom) - Maximum aperture: f/4 - Made for: APS-C sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Pentax K): like 24-68mm on full frame; f/4 gives about the depth of field of f/6 there. - On the larger-sensor bodies of Pentax K: ...

From Sigma 18-35mm f/1.8 DC HSM Art: Sigma 18-35mm f/1.8 DC HSM Art: A zoom lens by Sigma for APS-C cameras, 18-35mm f/1.8. Specs - Maker: Sigma - Focal length: 18-35mm (zoom) - Maximum aperture: f/1.8 - Made for: APS-C sensors - Mounts: Canon EF, Nikon F, Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Nikon F, Pentax K): like 27-52mm on full frame; f/1.8 gives about the depth of field of f/2.7 there. - On ...

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