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The Canon EF-S 18–200mm lens is a superzoom lens, manufactured by Canon. It is the higher end kit lens for the Canon EOS 60D digital camera, and supplants the previous EF-S 17–85mm, in Canon's product line-up, losing 1mm off the wide end, but offering a roughly 2.5x longer telephoto end. While Canon has produced superzooms for the full frame EF mount, they function only as normal length to long telephoto lenses on cameras equipped with APS-C sensors. This is the first EF-S lens made by Canon to offer both wide-angle and telephoto shooting range in the same package. Other manufacturers, including Sigma and Tamron have had similar lenses available for EF-S cameras for some time; however, their lenses generally only work at 6.3 when fully zoomed in, which can make autofocusing unreliable (Canon's APS-C cameras are only designed to autofocus up to 5.6). Canon's version is a third of a stop faster when fully zoomed in, which means that autofocusing is more reliable, and the lens is slightly faster as well. It is almost functionally identical to the Canon 28–300L lens, which also has image stabilization and comparable apertures and focal lengths when mounted on a 35mm (or full-frame) camera. Reviews indicate that the 18–200 does not compare to the 28–300L in terms of image quality, though this is understandable since the latter is priced much higher, due to it belonging to the L-series line. Most reviewers have criticised the lens for high levels of barrel distortion at the wide end, and chromatic aberration and softness evident at all focal lengths and apertures. The lack of an UltraSonic Motor has also been noted by reviewers, and along with the 18–55 IS has given rise to concerns that Canon may be moving towards removing USM from their lower-end lenses. It has generally been rated higher than Sigma and Tamron's offerings however, and has received generally positive reviews with the caveat that it is designed for convenience rather than image quality. A combination of similar-class EF-S lenses that covers this range of focal lengths is the EF-S 18–55mm and the EF-S 55–250mm. ==External links== *(Review at dpreview.com ) *(Review at photozone.de ) *(Review at the-digital-picture.com ) *(Anandtech: Canon EOS 50D overview ) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Canon EF-S 18–200mm lens」の詳細全文を読む スポンサード リンク
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