A known problem of the Lunt Blocking Filter in the diagonal is the tarnishing of the glass surface. While Lunt has promised a replacement, I am not sure if the problem will recur on the new glass. I have read that it is due to salt-laden moisture (although I live far from the sea); some even claim it is some kind of fungus. Yet another post I came across said that the deterioration of acrylic (?) material is caused by IR and UV rays which it encounters over time.
Does anyone know what causes this tarnishing, and whether Lunt has licked this issue in the new products?
Edited by KaiserT, 07 February 2019 - 02:58 AM.