Hi. On behalf of a friend. She has this old camera (see title - much loved), where the battery appears charged according to the charger but the camera fails to operate. I've noticed that both battery and charger show four contacts. Looking down into the battery compartment of the camera, there are only three metal contacts standing proud. There is a gap for a fourth but nothing there. Should there be four? (She's reluctant to give up on this old camera) The manual (remember those) doesn't offer any help. Would be grateful if anyone can confirm - thanks.