‘The question is’, said Humpty Dumpty, ‘which is to be master – that’s all.’
Through the Looking-Glass
Master holograms are the originals that are employed for making final display holograms. They are almost invariably laser transmission holograms. However, it may occasionally be necessary to produce a reflection master, and this may apply to full-color originals or some kinds of industrial holography. A master hologram is the holographic equivalent of a photographic negative and is unique in the same way. It facilitates the production of multiple copies; it is made with careful control of lighting balance, is replicated exactly in the copy, and makes possible the use of imaging effects ...