Pentax hd da 11 18mm f 2 8 ed dc aw vs pentax 10 17mm f 3 5 4 5?

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From Pentax HD DA* 11-18mm f/2.8 ED DC AW: Pentax HD DA* 11-18mm f/2.8 ED DC AW: A zoom lens by Pentax for APS-C cameras, 11-18mm f/2.8. A fast, weather-sealed wide zoom for APS-C. Specs - Maker: Pentax - Focal length: 11-18mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Pentax K): like 16-27mm on full frame; f/2.8 gives about the depth of field of f/4.2 there. - ...

From Pentax HD DA Fish-Eye 10-17mm f/3.5-4.5 ED: Pentax HD DA Fish-Eye 10-17mm f/3.5-4.5 ED: A zoom lens by Pentax for APS-C cameras, 10-17mm f/3.5-4.5. A fisheye zoom; the older smc version has the same optics.

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