The Tamron 70-200mm f/2.8 SP Di VC USD is a sharp lens, from corner to corner. There’s a reason that DXOMark list it as one of the best lenses (and best in its class at time of writing) to use on the Nikon D800. Please click on the image below to view it in its full 7360 x 4912 glory. It’s a single, uncropped FX frame processed in Adobe Camera RAW. Have a good look through, from the handrails along the Humber Bridge to the distant riverbank. Look for the boathouse, the yachts, and the pylons on the horizon. If that doesn’t convince you, I’m not sure what will.