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[[http://en.wikipedia.org/wiki/Holography#Hobbyist_use From Wikipedia:]] Since the beginning of holography, experimenters have explored its uses. Starting in 1971, Lloyd Cross started the San Francisco School of Holography has and started to teach amateurs the methods of making holograms with inexpensive equipment. This method relied on the use of a large table of deep sand to hold the optics rigid and damp vibrations that would destroy the image. Many of these holographers would go on to produce art holograms. In 1983, Fred Unterseher published the Holography Handbook, a remarkably easy-to-read description of making holograms at home. This brought in a wealth new wave of holographers and gave simple methods to use the then-available AGFA silver halide recording materials. In 2000, Frank DeFreitas published the Shoebox Holography Book and introduced the use of possibilities inexpensive laser pointers to countless hobbyists. This was a very important development for amateurs, as the cost for a 5 mW laser dropped from $1200 to $5 as semiconductor laser diodes reached mass market. Now, there are hundreds to thousands of amateur holographers worldwide. In 2006, a large number of surplus Holography Quality Green Lasers (Coherent C315) became available and professional put Dichromated Gelatin (DCG) within the reach of the amateur holographer. The holography community was surprised at the amazing sensitivity of DCG to green light. It had been assumed that the sensitivity would be non-existent. Jeff Blyth responded with the G307 formulation of DCG to increase the speed and sensitivity to these new lasers. Many film suppliers have come and gone from the silver-halide market. While more film manufactures have filled in the voids, many amateurs are now making their own film. The favorite formulations are Dichromated Gelatin, Methylene Blue Sensitised Dichromated Gelatin and Diffusion Method Silver Halide preparations. Jeff Blyth has published very accurate methods for making film in a small lab or garage. A small group of amateurs are even constructing their own pulsed lasers to make holograms of moving objects. Holography kits with self-developing film plates have now entered the consumer market. The kits make holographs and have been found to be fairly error tolerant, alikeand enable holograms to be made without any other specialized equipment.