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早在传统影像时代,佳能就曾经开发出EF 1200mm f/5.6L USM镜头,这是迄今为止焦距最长的自动调焦镜头,可惜这款巨无霸现已停产。2008年初,佳能发布了新款超长焦镜头——EF 800mm f/5.6L IS USM,新镜头虽说焦距比那款1200mm的镜头有所缩短,但是其光学性能却有了明显提高,更重要的是它增加了防抖功能。这款800mm的镜头采用14组18片的光学设计,内含2片萤石镜片以及1片超级UD、1片UD镜片。这些特殊镜片不但能很有效地修正色差,而且为镜头小型化做出了很大贡献,以至于这款800mm的超级“大炮”甚至与自家EF 600mm f/4L IS USM镜头大小相差无几。在各大厂商的“大炮”群中,佳能EF 800mm f/5.6L IS USM镜头的焦距指标名列前茅,只有适马两款焦距达到800mm的镜头能够与其相提并论。
As early as the traditional imaging era, Canon had developed the EF 1200mm f / 5.6L USM lens, which is by far the longest focal length auto-focus lens, but this giant has now discontinued. In early 2008, Canon released the new ultra-telephoto lens - EF 800mm f / 5.6L IS USM, although the new lens focal length than that 1200mm lens has been shortened, but its optical performance has been significantly improved, more importantly It adds anti-shake function. This 800mm lens with 14 sets of 18 optical design, contains two fluorite lenses and a super UD, a UD lens. Not only did these special lenses correct chromatic aberration effectively, but they also contributed greatly to the miniaturization of the lens so much that the 800mm Super Cannon was almost the same size as its own EF 600mm f / 4L IS USM lens. Among the major manufacturers of “cannon” group, the Canon EF 800mm f / 5.6L IS USM lens focal length index among the best, only two of Sigma’s focal length up to 800mm lens can be compared with them.