I built one such camera from a discarded Kodak that had a film opening almost the size of 4x5 film... I replaced the bellows with a fixed cone, the 170mm lens with a 90mm extra wide angle lens in a self-cocking shutter, and replaced the rollfilm back with a brass pocket lined with felt to accept a film holder. It is, quite literally, just point and shoot, and let the depth of field take care of the rest.