Message text written by INTERNET:[EMAIL PROTECTED]
>Third-party companies do make real AF TC's.
In fact, almost everybody BUT Nikon makes AF
TC's. I don't know which (if any) of them
would be a good match with the 300mm/f4.<<<<
Actually, there are several manufactureres who don't make autofocus TC's,
much to the disappointment of their customers. The manufacturers are
worried about the extra drag on the focusing motors, and the possibility of
slop in the additional couplings. This is where the lens-mounted motors
have the advantage.
I have used the Kenko 1.5x autofocus TC with the 80-200, and it retains the
sharpness of that lens surprisingly well for a piece of equipment that only
costs $69. It even improves the exposure evenness, as the TC only takes
the portion of the image from the center of the light cone. I don't expect
miracles from it, and I don't know how well it would work with the 300, but
it might be a cost-effective solution. Kenko also makes a couple of 2x AF
converters. Reviewers are constantly giving the Kenko TC's outstanding
reviews, especially considering their low prices. It is a shade less sharp
than the best Nikon 1.4x TC, and of course not as solidly built, but at a
fraction of the price. Thoroughly test it with the lens you want to use it
with, though, as a TC that works well with one lens may be a dog with
another. -BC-
