The Tamron SP 24-70mm USD lens is a high grade, fast aperture standard zoom lens featuring superb optical performance and ultra-fast, quiet focusing.
Ultrasonic Silent Drive
Uses the ultrasonic method as opposed to a traditional motor, which allows the use of a continuous manual (override) mechanism and makes focusing ultra fast and quiet.
The Tamron SP 24-70mm USD lens produces class-leading image quality and this is no accident. It includes three LD (low dispersion) elements, three glass-moulded aspherical elements, one hybrid aspherical lens and two XR (Extra Refractive Index) glasses to both cut down on aberrations (inaccuracies and distortions) and improve compactness.