Laser discs

Several laser discs at this site have drop-out and are unplayable,
although the more recent discs (1987 and up) are still in fine
condition.  Was there a change in process between 1983 and 1987 or is it
just the aging process?

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                  Conservation DistList Instance 7:44
                 Distributed: Monday, December 13, 1993
                        Message Id: cdl-7-44-005
                                  ***