A ring-type Ultrasonic Motor (USM), along with an internal focusing system, high-speed CPU, and optimized AF algorithms, are employed to deliver fast, precise, and near-silent autofocus performance as well as full-time manual focus override.

As a member of the esteemed L-series, this lens is sealed against dust and moisture for working in inclement environmental conditions.

Protective fluorine coating has been applied to the front bulbous element to resist fingerprints and smudges and to make cleaning significantly easier.

Rounded nine-blade diaphragm contributes to a pleasing out of focus quality that benefits the use of shallow depth of field and selective focus techniques.