[solissydney (Ken)]

Hi.
My telrad, finder and guide scope sits next to each other on my scope.
Both the finder and guide scope have 15 - 20 cm cardboard dew shields attached.
I found a substance, like very fine sand paper, or , like a fine mist from a spray can, on the front lens of the finder and also on the telrad, but not on the guide scope? Nothing will remove the stuff, not, soap and water, kerosine, turps, metho and glass cleaner??? What's left to try, sand paper???
Any clues?
Ken