Pentax hd da 11 18mm f 2 8 ed dc aw vs pentax 12 24mm f 4?

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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 Landscape: Lenses: - A wide zoom, around 16-35mm on full frame or 10-24mm on APS-C, is the classic landscape lens: big skies, strong foregrounds. - A standard zoom, 24-70mm or similar, covers most scenes. - A telephoto zoom, 70-200mm or longer, is underrated: it picks out layers of hills, a lone tree, or light on a distant ridge. You don't need fast apertures for landscapes, since you'll usually shoot between f/8 and ...

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