17-35mm F2.8-4 EX DG ASPHERICAL HSM is specially designed to suit the characteristics of digital SLR cameras.This lens has a compact dimensions that features overall length of 86.2mm/3.3in. SLD (Special Low Dispersion) Glass is used for effective compensation of color aberration. Two pieces of molded glass aspherical lens elements offer excellent correction for distortion as well as all types of aberration. Excellent optical performance was realized both for Digital SLR cameras and film SLR cameras.
The 17-35mm lens has a minimum focusing distance of 27cm / 10.6in. at all focal lengths, and maximum magnification ratio of 1:4.5. This super-wide angle lens' useful range of view is very convenient for close-up photography. An inner focus system provides high performance and convenience. The non-rotating lens barrel perfectly suits the matched petal shaped lens hood.
The lens mounts for Sigma, Nikon and Canon are equipped with Hyper Sonic Motor (HSM). It is easy to revert to Manual Focus by simply turning the focusing ring and overriding the AF. An inner focus system provides high performance and convenience. The inner focus system allows the lens to be focused without having to rotate the front of the lens, so the lens accepts a Petal-type hood and it is also easy to use a circular polarizing filter.
Lens Technology Explained:
ASP (Aspherical Lens)
The aspherical lens complex allows freedom of design, improved performance, a reduced number of component lenses and a compact size.
HSM (Hyper-Sonic Motor)
This lens uses a motor driven by ultrasonic waves to provide a quiet, highspeed AF.
IF (Inner Focus)
To ensure stability in focusing, this lens moves the inner lens group or groups without changing the lens' physical length.
EX (EX Lens)
The exterior of this lens is EX-finished to denote the superior build and optical quality, and to enhance its appearance.
DG for Digital (DG Lens)
These are large-aperture lenses with wide angles and short minimum focusing distances. With an abundance of peripheral illumination, they are ideal lenses for Digital SLR Cameras whilst retaining suitability for traditional 35mm SLRs.
Lens Construction: 16 Elements in 13 Groups
Angle of View: 103.7 - 63.4 degrees
Number of Diaphragm Blades: 8 Blades
Minimum Aperture: F22
Minimum Focusing Distance: 27cm / 10.6 in.
Maximum Magnification: 1:4.5
Filter Size Diameter: 77mm
Dimensions: Diameter 83.5mm x Length 88.7mm / 3.3 in. x 3.4 in.
Weight: 560g / 19.8 oz.