Hi guys, just wanted to chime in here. According to Wikipedia the A-mount flange distance is very close to the EF-mount. Nikon's is longer. This means that, although there are no adapters currently on the market, there definitely could be, at the very least passive ones. There are F-mount to EF-mount adapters available and people do successfully use them so I see no reason why 0.5mm would make a difference in the feasibility of an F-mount to A-mount adapter.