Thanks for the information, and after reading the first post I ended up at the Kenko Pro, will this TC also work on my 70-300 vr?
I tried the combination of a D200, 70-300mm VR and a Kenko 1.4x DG teleconverter. It all fits together fine, and the camera meters and shoots normally. Autofocus operating is sluggish even in full sunlight and rapidly becomes unreliable as the amount of available light decreases.
But at least in my own tests, I found the results using this TC with the 70-300mm VR were not significantly better than simply cropping. I continue to use the teleconverter with the 180mm f/2.8, 300mm f/4, and the 70-200mm VR.
One of the biggest mistakes a photographer can make is to look at the real world and cling to the vain hope that next time his film will somehow bear a closer resemblance to it. - Galen Rowell