The Tamron 100-400mm F/4.5-6.3 Di VC USD is a very versatile telephoto zoom lens for full-frame and APS-C DSLR cameras. Costing much less than rival lenses from Nikon and Canon, whilst being lighter and more compact, is this new Tamron 100-400mm lens worth considering? Read our in-depth Tamron 100-400mm F/4.5-6.3 Di VC USD review, complete with full-size sample images, to find out...