Tamron 18 400mm f 3 5 6 3 vs nikon 18 300mm f 3 5 6 3?

Here is what the site says about that.

From Tamron 18-400mm f/3.5-6.3 Di II VC HLD: Tamron 18-400mm f/3.5-6.3 Di II VC HLD: A zoom lens by Tamron for APS-C cameras, 18-400mm f/3.5-6.3. An all-in-one zoom reaching 600mm equivalent (640mm on Canon).

From Tamron 18-300mm f/3.5-6.3 Di III-A VC VXD: Tamron 18-300mm f/3.5-6.3 Di III-A VC VXD: A zoom lens by Tamron for APS-C cameras, 18-300mm f/3.5-6.3. One lens from wide angle to 450mm equivalent (480mm on Canon): an APS-C travel zoom.

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