Canon rf 20 50mm f 4l is usm pz vs tamron 16 50mm f 2 8 a?

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From Canon RF 20-50mm f/4L IS USM PZ: Canon RF 20-50mm f/4L IS USM PZ: A zoom lens by Canon for Full frame cameras, 20-50mm f/4. A full-frame video zoom with a built-in power zoom you can switch to manual. Specs - Maker: Canon - Focal length: 20-50mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon RF): as marked, 20-50mm. - On APS-C ...

From Tamron 16-50mm f/2.8 A: Tamron 16-50mm f/2.8 A: A zoom lens by Tamron for APS-C cameras, 16-50mm f/2.8. A 305-gram constant f/2.8 standard zoom for APS-C mirrorless bodies. Specs - Maker: Tamron - Focal length: 16-50mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Nikon Z, Fujifilm X, Canon RF - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E, Nikon Z, Fujifilm X): like 24-75mm on ...

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