http://www.nikonchat.com/nikon-digital-teleconverter/

I have a 18-200mm Lens nikon digital slr. What teleconverter would work best for this?
I have a 18-200mm Lens Nikon digital SLR. I'm looking for let me bring something much closer. Is there some kind of teleconverter which could connect to it? Or do I have to save for a 400 mm lens or 600 mm?
You can get a 2X teleconverter that essentially double your focal length to 400 mm. In my opinion, autofocus slows some, but not so bad. At 400mm you should use a tripod or monopod to steady the camera and lens
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