What happens during the exposed holographic material processing?
The exposure forms in the holographic emulsion the very faint record (latent image) of the exposed object. To make this latent image visible – the emulsion has to be developed and bleached. Developing: The crystals (grains) of silver bromide in the emulsion are reduced to black metallic silver. First Wash in Water: This removes all traces of developer. Bleaching: This process oxidizes the silver image to silver bromide, the emulsion now becoming transparent again with a slightly milky appearance. Second Wash in Water: This removes all traces of bleach. Drying: Removes water from developed and bleached emulsion structure and the hologram becomes visible when illuminated by spot light source. Note: Ultrafine grain emulsions needs an additional operation – the hardening.
