I've been given some Metone "photo-sensitised aluminum plates for line or continuous tone". They were made by John Blishen & Co. Ltd. They are Orthochromatic and, according to the box, should be processed using a red safe light. They are 13 x 18 in size. assuming that there is any life left in them (I have no idea how old they are) what could I use them for?
Pete.