Tamron 50 400mm f 4 5 6 3 vs nikon z 100 400mm f 4 5 5 6 vr s?

Here is what the site says about that.

From Nikon Z 100-400mm f/4.5-5.6 VR S: Nikon Z 100-400mm f/4.5-5.6 VR S: A zoom lens by Nikon for Full frame cameras, 100-400mm f/4.5-5.6. Specs - Maker: Nikon - Focal length: 100-400mm (zoom) - Maximum aperture: f/4.5-5.6 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Nikon Z - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Nikon Z): as marked, 100-400mm. - On APS-C (Nikon Z): like 150-600mm on full frame; ...

From Tamron 100-400mm f/4.5-6.3 Di VC USD: Tamron 100-400mm f/4.5-6.3 Di VC USD: A zoom lens by Tamron for Full frame cameras, 100-400mm f/4.5-6.3.

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