Hello there! I need some help. I recently purchased a 645n system and I am having a hard time pulling the battery holder out. It looks pretty basic, Lift up the battery holder knob and turn it in the direction of the arrow. For some reason, it will not come out. In the small gap between the body and the battery holder I can see a metal plate (which I think serves as the lock, and retracts to unlock it.) It does not move even if I turn the knob. It does not look like that there is an old battery inside. Am I doing it wrong? Do i have to hold or press anything? Do I have to put it on any setting?
I should have checked it before paying but it was such a good deal that I just want to get it done and leave. The purchase includes the body with FA 75 2.8, FA 80-160, AF500 FTZ flash, 120 and 220 backs, lots of film, a Tamrac rolling backpack, filters. All in excellent condition 9.5/10 for $220.
Thanks and have a nice day!