What are the alternatives to the pentax hd da 20 40mm f 2 8 4 ed limited dc wr?

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From Pentax HD DA 20-40mm f/2.8-4 ED Limited DC WR: Pentax HD DA 20-40mm f/2.8-4 ED Limited DC WR: A zoom lens by Pentax for APS-C cameras, 20-40mm f/2.8-4. The only zoom in Pentax's Limited range, in a small metal barrel. Specs - Maker: Pentax - Focal length: 20-40mm (zoom) - Maximum aperture: f/2.8-4 (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 30-60mm on full ...

From Pentax HD D FA 21mm f/2.4 ED Limited DC WR: Pentax HD D FA 21mm f/2.4 ED Limited DC WR: A prime lens by Pentax for Full frame cameras, 21mm f/2.4. A compact, weather-sealed wide prime for the full-frame bodies.

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