Just an observation. Over many years of using binoculars of all sorts, both CF and IF, particularly as I delved into "playing around" with older and used binoculars, I found IF binoculars degrade internally far less than CF binoculars. That, of course, comes as no surprise to experienced users who understand the mechanical properties involved. And where the binocular has spent its life, on the coast or in high humidity areas as opposed to the desert southwest or rocky mountains also contributes to less degrading.
Whenever I see fungus on a lens or prism, I'm willing to bet that it didn't live in Arizona. IMO it is unrealistic for users to expect binoculars used and stored in various locations subjected to constant barometric pressure changes to remain pristine internally. After all we aren't talking about vacuums inside binoculars - maybe in the laboratory but not in the field.
I also hold the opinion that the "tighter" the internal mechanisms and lens seats, once the "bad stuff" gets in, the more difficulty getting it out.
One CF which claims H2O proof which has intrigued me is the now discontinued Leupold Cascade porro. I had several over the years and still have the 8x42 model. It of course is an Opticron clone. I won't live long enough to learn whether it will live up to its claim, but I am curious. IMO opinion, other than a lesser FOV, it is vastly underrated as a binocular and matches any alpha I have seen power for power.
John
