transportation of a lithographic plate uses an indexer to load plates into pods for delivery to a press cylinder via a pod elevator or a pod cart . the plates are imprinted with a bar code , imaged , punched , bent , sheared , corner notched , and registered to a press cylinder . the plates are loaded into the indexer , which moves the loaded plates into a position in alignment with designated pod compartments , and loads the plates into each of the designated pod compartments by indexed movement of an elevator within the indexer . the pod elevator or the pod cart moves the pods proximate to a press cylinder where the plates are unloaded from the pod and loaded onto a press cylinder . a computing device , such as a plc , directs the process . a vision system senses information from the indexer , pod , pod elevator , and the plate for feedback to a plc , which initiates all of the foregoing operations .