I don't know much but... there seems to be several types, with both blue, green, red and pancro sensitive emulsions. I can't see why they wouldn't be able to be used as normal plates as they seem to have a daylight spectrum sensitivity. The developer I found looks rather like a normal B/W developer to a non-chemist: http://www.holokits.com/jd-2_holography_developer.htm. Why not give it a go if you have a bunch of the plates lying around.

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