Quote Originally Posted by Trowski


Keep in mind there's more to performance with the 2x III than just image quality. If focusing speed and tracking ability is greatly improved, I would say some of the hype about the new lenses and extenders would be justified.

I had bought the 1.4x III a while back, and I went back and read my notes as to why I returned it. The IQ on the current version of the 500mm was almost identical to the 1.4x II, very little if any improvement. However, I had problem's with the new teleconverter tracking properly on the 500mm. I was loosing allot of moving targets that the 1.4x II didn't have a problem with.


Since they extender III'sare designed for the new lenses, maybe there will be improvementwith that combination over the old lens combinations.