The Sigma 17-70mm f/2.8-4 DC Macro HSM Lens for Sony is a
standard zoom lens designed especially for DSLRs with APS-C-sized image
sensors. This lens has a 35mm-equivalent focal length range of
25.5-105mm, providing wide-angle to portrait-length angles of view for
use in everyday shooting situations.
This lens features a fast
f/2.8-4 maximum aperture to help better control your focus plane and to
aid in low-light shooting. The Hyper Sonic AF Motor delivers fast,
smooth, and quiet auto focusing that greatly benefits video
applications. The integration of two FLD, one SLD, and three aspherical
lenses in the construction helps to reduce the effects of chromatic and
chromatic axial aberrations, and Super Multi-Layer coated elements help
to increase contrast for sharp, clear imagery.
As part of
Sigma's new Contemporary line of lenses, this lens is designed using
Thermally Stable Composite (TSC) materials to help reduce the overall
weight and size of the lens barrel by about 30% without compromising on
optical integrity, rigidity, or overall durability.