Can anyone advise me about the functions of the 2 potentiometers on the Yashicamat 124G light meter? I suspect one is gain and the other offset, but I could be way off base. Mine reads too dark by about 4 stops. It appears that the switch works properly and I am using a hearing aid battery with adapter. Yes I have a good hand held meter, but would like to get the built in meter working at least in the ball park. Any help with adjustment would be appreciated.