Paterson PTP125 Changing BagA changing bag is probably the most essential piece of equipment a photographer who shoots with film can carry. In the field having a changing bag to hand means that a jammed or partly exposed film can be safely removed from the camera and shooting can continue. It will also allow a film to be loaded into a developing tank without having to first find a darkroom. The Paterson changing bag is large enough to allow a camera back to be fully opened once