Other day, lens on the ZIESS conquest went black. Couldn't see through it. It was cold humid morning where optics would be prone to fogging.
This was like a coating of soot, I had to almost scrub the gunk off so I could see through it. Anyone got a clue to what happened?
I wonder if the lens coating somehow had a reaction and went black

Zeiss Conquest 4.5-14x50 AO MC w/ target turrets
