Methods, systems and computer program products for retrieving mental images of faces from the human brain. The methods and structures include the use of digital filters that provide a digital representation of the residue of a preceding converter cycle, multiply this representation by an appropriate memory parameter, and sum the product with the digital representation of the residue of a current converter cycle to thereby reduce the memory effect. The method for loading the printing plate material supply spool in a printing machine or plate imaging machine may comprise inserting a heavy-duty core inside the HC of the PMSS forming an integrated core.