I am looking into buying a teleconverter for my nikon d90 with the 70-300mm G non vr lens. I have read numerous articles and am still confused. My question is, "Will a teleconverter work with this combination?" and "Will the autofocus still work?" I apologize if this has been asked before, but I couldn't find a thread that answered my questions. Any help would be appreciated. Thank you in advance.