The tamron 70 200mm f28 sp di vc usd lens canon fit is a high speed telephoto zoom lens with an ultrasonic silent drive that achieves leading edge image quality while boasting the most compact design in its class the usd ultrasonic silent drive delivers speedy af autofocus and the moisture resistant construction helps keep the rain out the design features 23 elements on 17 groups including four low dispersion glass elements for minimising chromatic aberration vibration compensation prov