In the second picture, I am intrigued by the shirts worn by four of the men. The man on the extreme right is wearing a standard issue khaki drill shirt but the other four seem to be wearing some sort of sporting shirt. Note the white(?) piping at neck and sleeves, however, they all appear to be wearing issue shorts. For some reason, just a gut feeling really, Polo is the sport that comes to mind. Also, the man at the front left looks to be holding a fly swatter, whilst behind them the large tree looks very much like a conifer of some description. I can't remember ever seeing conifer trees in the far east, so could this picture have been taken whilst they were in transit, maybe the Middle East? I have a photograph of a relative wearing pretty much an identical helmet to the one held by the man on the right, when he was serving in N.Africa with the 8th. Army. Not much help in distinguishing between your uncle and your father but hopefully something I have said may give a lead somehow.