Pentax smc da 16 45mm f 4 ed al vs tamron 17 50mm f 2 8?

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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 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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