Crystalline structures in lens?

Started by dmcgough, 03/06/2012 12:34AM
Posted 03/06/2012 12:34AM Opening Post
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
Posted 03/06/2012 02:45AM #1
David McGough said:

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

Can you see it? Then you don't have to worry about it.


Posted 03/06/2012 10:17PM #2
Without a pix, I have nothing to go on.

Roland