Still very much in my 'honeymoon' period with my U2. Got up this morning thought of putting on the Ingenieur but somehow my hands naturally reached for the U2
Anyway, I was going thru some of the materials during my research and came upon a statement by Sinn that the AR coating on the U2 is 1800HV.
quote in verbatim
"Extra hard anti-reflective coating of 1800HV on the outside"
My question is how this is done, tegiment ? ...is that even possible to do that on a crystal.