Tamron's SP 24-70mm f/2.8 DI USD Lens for Sony Cameras delivers a very useful range from 24mm true wide-angle to 70mm short telephoto, useful for landscapes, interiors, portraits, street photography and much more. The continuous maximum aperture of f/2.8 makes it possible to achieve stellar results in low-light situations, while the Ultrasonic Silent Drive (USD) gives you very quiet autofocus capabilities that are ideal for shooting video. The 24-70mm lens uses specialized high-grade glass in the three LD elements, three Glass Molded Aspherical Lenses, one Hybrid Aspherical Lens and two XR (Extra Refractive Index) glasses, for excellent image quality. Using a rounded 9-blade diaphragm, the lens delivers fine bokeh--the out-of-focus area in a photo. Moisture-resistant construction helps protect the lens from any water that comes near it. And all of this is in a compact (3.5 x 4.6"), lightweight (29.1 oz) package that won't wear you out, even carrying it all day. Uses specialized high-grade glass in the three LD elements, three Glass Molded Aspherical Lenses, one Hybrid Aspherical Lens and two XR (Extra Refractive Index) glasses, delivering top-of-the-class quality images suited to this high-grade lens. Using a rounded diaphragm, the lens achieves gorgeous blur effects.Features USD (Ultrasonic Silent Drive) to power a speedy AF drive together with a continuous manual mechanism.This high-speed standard zoom lens has a wide-end focal length of 24mm that expands the photographic area.The lens adopts the latest optical design USD (Ultrasonic Silent Drive) in a lighter and more compact package.Moisture-resistant construction helps prevent water from penetrating the lens.In the ultrasonic motor, a piezoelectric element arranged in a ring formation generates ultrasonic vibrations in a metallic ring stator, and the vibration energy is used to rotate a metallic ring rotor that is attached to the stator. The rotation energy is in turn transferred from the metallic ring rotor to operate the focus
