Traditionally, lens makers like to mark the location of the company conspicuously on their lenses. Therefore, from the beginning of lens manufacture up to the end of the Second World War, all Zeiss lenses were marked "Carl Zeiss Jena". Since the new Oberkochen-based Carl Zeiss Optical company is not in Jena, its products are simply marked "Carl Zeiss", while the original factory carried on using the "Carl Zeiss Jena" marking. For the first few years Carl Zeiss of Oberkochen used the "Zeiss-Opton" marking.