@scottbb The case is that the vast majority of mount adapters do not handle AF very well, if they even have provision to provide it. There are a few exceptions that work fairly well, but pretty much none that work as well as native lenses. Please note: there needs to be a different name for "adapters" that fit between lenses and cameras that use the same protocol and are only needed to provide proper spacing but don't have to translate signals between camera and lens and vice-versa.