Hello everyone. I have a former model of a Wista SP metal camera (Wista 45 D) an d would like to buy a roll-film (6x9) adapter. The camera is, to me identical to the Wista 45 SP. There are two kind of roll film holder from Wista: "Rollfilm Holders for Sliding Back" and "Rollfilm Holders 4x5" mount". Which one is for what? Why should I choose one instead of the other? I would app reciate help from anyone about this accessory since information on the Wista sit e is rather lacking.
TIA Ciao Roberto