Hi,
In ad 768077 for an old 5" f6 NASA glass triplet, there is mention of "VERY beginning amount of crystalline structures in the lens".
What is this referring to, devitrification of some sort? Is this something peculiar to this old NASA glass and that those of use with later EDTs and the like never need to worry about?
Dave
In ad 768077 for an old 5" f6 NASA glass triplet, there is mention of "VERY beginning amount of crystalline structures in the lens".
What is this referring to, devitrification of some sort? Is this something peculiar to this old NASA glass and that those of use with later EDTs and the like never need to worry about?
Dave