This is a standard zoom lens covering a wide range from 24mm wide-angle to 105mm medium-telephoto shooting. In addition to achieving a broad zoom range, the optical system made up of 18 elements in 13 groups contains only environmentally-friendly lead-free glass. The various types of aberration are well compensated using one super UD lens and three aspherical lenses (replica and molded glass), and this enables high quality images befitting L-series lenses. In addition, optimization of lens positioning and coating minimizes the flare and ghosting to which digital cameras are susceptible, while an image stabilizer mechanism is incorporated to offer camera-shake compensation for approximately three shutter speed steps. Furthermore, the highly dust-proof and drip-proof*¹ structure enabling shooting in harsh conditions, and full-time manual focusing make this a high-performance lens able to meet the high demands of professionals and highly skilled amateurs.