Tamron has announced the development of the world’s smallest and lightest telephoto zoom lens for full-frame Sony E-mount cameras: the Tamron 70-300mm F/4.5-6.3 Di III RXD. “While Tamron has manufactured many popular telephoto zoom lenses that extend to 300mm for DSLR cameras, the new 70-300mm F4.5-6.3 is the first model …