Pentax hd da 18 50mm f 4 5 6 dc wr re vs pentax 16 50mm f 2 8?

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From Pentax HD DA 18-50mm f/4-5.6 DC WR RE: Pentax HD DA 18-50mm f/4-5.6 DC WR RE: A zoom lens by Pentax for APS-C cameras, 18-50mm f/4-5.6. Specs - Maker: Pentax - Focal length: 18-50mm (zoom) - Maximum aperture: f/4-5.6 (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 27-75mm on full frame; f/4-5.6 gives about the depth of field of f/6-8.4 there. - ...

From TTArtisan 50mm f/2: TTArtisan 50mm f/2: A prime lens by TTArtisan for Full frame cameras, 50mm f/2. Specs - Maker: TTArtisan - Focal length: 50mm (prime) - Maximum aperture: f/2 - Made for: Full frame sensors - Mounts: Sony E, Fujifilm X, Nikon Z, Canon RF, L-Mount, Micro Four Thirds - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E, Nikon Z, Canon RF, L-Mount): as marked, 50mm. ...

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