Tamron 28 200mm f 2 8 5 6 di iii rxd vs sigma 20 200mm f 3 5 6 3?

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From Tamron 28-200mm f/2.8-5.6 Di III RXD: Tamron 28-200mm f/2.8-5.6 Di III RXD: A zoom lens by Tamron for Full frame cameras, 28-200mm f/2.8-5.6. A full-frame travel zoom that starts at f/2.8. Specs - Maker: Tamron - Focal length: 28-200mm (zoom) - Maximum aperture: f/2.8-5.6 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 28-200mm. - On ...

From Tamron 28-75mm f/2.8 Di III RXD: Tamron 28-75mm f/2.8 Di III RXD: A zoom lens by Tamron for Full frame cameras, 28-75mm f/2.8.

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