Question from John Burnley
Do you know if the 100-400 zoom will autofocus with the new Panasonic 2x converter or 1.4X converter?
Have you tried either for sharpness? I know the lens by itself is very sharp at the 400mm setting.
John, Sorry for the late reply. Unfortunately, the 100-400mm will not work with the new Lumix teleconverters. In general, putting more glass in front of a lens that already contains a lot of glass is not a great idea. It’s possible that a new 100-400mm may be developed at some point that would allow teleconverter use. Olympus has announced just such a lens their in development 150-400mm to be rele3ased in 2020. It actually has a builtin teleconverter and could be a class leading lens.