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Old 11-01-08, 12:06
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Don Hoey Don Hoey is offline  
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Quote:
Originally Posted by Chris View Post
seems odd that the Nikon teleconverters don't work;
Chris,

Its all down to design. I have neither the 18-200 or the TC-14E II but if you check the lens construction images at the bottom of the page on each of these links, you can see that there would be a clash of elements between the lens and the converter.

http://nikonimaging.com/global/produ...g_if/index.htm
http://nikonimaging.com/global/produ...4e_2/index.htm

On the Kenko converter the design is such that the front element of the converter is 8mm inside the mounting flange. Whether that 8mm is sufficient clearence I do not know.

The other factor to be taken into account is aperture. In Thom Hogans review effective aperture falls off quite sharply, f4.8 by 50mm, so adding a tc will have an effect on the ability of the lens to satisfactorily auto focus. Link to Thom Hogans review http://www.bythom.com/18200lens.htm

Don
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