AF-S TELECONVERTER TC800-1.25E ED primary features
Designed exclusively for use with the AF-S NIKKOR 800mm f/5.6E FL ED VR. This teleconverter has been designed to produce images exhibiting the same rendering performance as the primary lens.
When used with the AF-S NIKKOR 800mm f/5.6E FL ED VR, focal length is increased by 1.25x for a focal length of 1000 mm (combined maximum aperture of f/7.1).
>>>>The first teleconverter equipped with an ED lens element.<<<<<
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有 ED lens 的 TC
http://www.nikon.com/news/2013/0129_lens_06.htm
