Canon EF-S 17-85mm f/4-5.6 Image Stabilized USM SLR Lens for EOS Digital SLR's

Canon's EF-S 17-85mm f/4-5.6 IS USM is an advanced compact, all purpose zoom lens specifically designed to be lightweight and versatile.  It features a   a focal length equivalent to 27-136mm in the 35mm format. It is compatible with DSLR cameras that use the APS-C format and provides a versatile set of focal lengths from wide-angle to telephoto.  Designed specifically for digital photography, it has a 17 element, 12 group construction, including one double-sided aspherical element for reduced aberrations and crisp, high contrast corner-to-corner detail. Canon's unique lens coatings suppress ghosting and flare and an optional dedicated lens hood can further reduce the incidence of flare. The rounded 6-blade aperture provides pleasing out-of-focus backgrounds when shooting with a shallow depth of field.

Canon's USM lenses employ a motor powered by ultrasonic waves that produce a quiet, yet high-speed AutoFocus. You can enjoy high performance with low noise in a variety of shooting situations. 

  

ULTRA LOW DISPERSION GLASS (UD)   

Canon's Low Dispersion technology is engineered to reduce chromatic aberrations, eliminating the tendency of light of different colors to focus to different points at the image plane.  This means your images will come out crisp and clear, with less of a chance of defracting light into an unwanted rainbow of colors.  Take shots exactly like you want, without any flare-up or blurring. 

Canon's aspherical lens design creates a more complex surface profile.  This helps to greatly reduce spherical and other optical aberrations.  The design further ensures consistent imaging performance throughout the entire focal range, while delivering incredible sharpness up to the periphery of the image.  

Manual focusing means you have all the control at the end of your fingers.  Canon lenses feature a specially designed ergonomic construction that is noticeable at first touch.  The large rotation angle of this lens guarantees precise focusing.  The mechanism moves super smoothly and without extra play, furthering the intuitive interaction along the focal plane.   

ADVANCED APERTURE DESIGN 

The circular aperture produces a natural background blur.  With Canon lenses you can create stunning Bokeh effects, thanks to the finely tuned features and advanced optical design.  By keeping the background intentionally blurred, additional focus is created on the subject of an image.  The uniquely engineered diaphragm blades of this lens, along with the virtually circular aperture, deliver stunning renditions of highlights the back and foreground. 

The Canon anti-reflective coating is an optical design feature which ensures superior clarity and image brilliance, even in poor or unfavorable lighting conditions.  Canon applies the anti-reflective coating through a special process, layering the lens surface in order to substantially reduce unwanted flare or ghosting.  This process helps to ensure incredibly rich image contrast and true color fidelity.  Canon L Series lenses feature a fluorine coating on the front and rear surfaces.  This coating helps to greatly reduce smears, smudges or fingerprints ensuring that you will always take impeccable images. 

Lens features Optical Stabilization technology, a feature that employs an innate, built-in mechanism in order to compensate for camera shake.  By eliminating natural shakes and sways with camera movement your images will come out crisp and clean every time.