Sigma 18 300mm f 3 5 6 3 vs tamron 16 300mm f 3 5 6 3?

Here is what the site says about that.

From Sigma 16-300mm f/3.5-6.7 DC OS Contemporary: Sigma 16-300mm f/3.5-6.7 DC OS Contemporary: A zoom lens by Sigma for APS-C cameras, 16-300mm f/3.5-6.7. An 18.8x all-in-one travel zoom for APS-C.

From Tamron 16-300mm f/3.5-6.3 Di II VC PZD Macro: Tamron 16-300mm f/3.5-6.3 Di II VC PZD Macro: A macro lens by Tamron for APS-C cameras, 16-300mm f/3.5-6.3.

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