so i'm using an old press camera and i cant figure something out. its an old speed graphic press camera and there is something to turn right behind the viewfinder. below the thing that turns there is like a switch that can move up and down from TRIP, BACK & FRONT. the switch is permanently on FRONT. unfortunately when i turn the dial there is this thing that comes down where the film would go, thereby not allowing the picture to be taken. i cant even open the back to focus b/c all i see is black. sorry for not being anymore help on this, but its really hard to explain.