In response to demands of photographers, the Canon EF-S 18-55mm f/3.5-5.6 IS Lens is designed with Canon's Optical Image Stabilizer technology while retaining the compactness and lightness of previous models. Its stabilization allows sharp hand-held shots at shutter speeds up to four stops slower than otherwise possible. It consists of 11 elements in 9 groups and uses an Aspherical lens element to correct aberration for excellent image quality throughout the zoom range and a circular aperture for exquisite rendering of out-of-focus backgrounds. Without a lot of size, weight or cost, this lens expands picture-taking possibilities any time slow shutter speeds are needed.
This is the magnifying factor of a lens. Macro lenses will often be described by their “magnification factor”. A lens with a 1:1 magnification factor produces a projected image on the sensor which is the same as the subject.
The individual pieces of glass that form the overall optical construction. Most lenses have between four and eleven elements to bend the light rays to ensure a perfectly formed image appears on the light sensitive surface, such as a film or CCD. The elements are arranged in groups and may be seen in specification sheets as, for example, 6 elements in 4 groups. That configuration may have two single elements and the other four grouped in pairs.