Re: BC flip up tight on NF eyepiece?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pazzo</div><div class="ubbcode-body">It's OK to use Acetone on your scopes glass?? </div></div>
Pretty much the std way to clean optics but I'd check w/mfg first. Takes some practice though and really needs to be done under magnification. I use an optivisor with an attached loupe and under a color-correct fluorescent light although it isn't strictly necessary. It works so well because it evaporates almost instantaneously as opposed to isopropyl alcohol for example and leaves no residue. I just use the stuff in the can at Wal-Mart, nothing special except to keep from getting it contaminated.
Gotta use
wooden cotton tipped swabs and a
pump dispenser to make it really safe for the optics. And use a swab exactly once and never put it back in the acetone pool in the dispenser cap if it's been used. Rule number two - see rule number one.
Trick is to get just enough to float any remaining particulates off the surface without causing scratches, trapping them in the swab instead, which is why you don't want to use the sort of swabs that are tightly wrapped as they aren't very absorbent. Applied lightly to the center, looking much like a mop at first when really soaked with lots of acetone, and then carefully spiraled outward to the edges the lens surface is progressively cleaned. It can take a _lot_ of swabs to do one surface, BTW. And as it gets cleaner you'd use less and less acetone soaked up in the swab tip until the surface is dead clean with maybe the faintest of spots out near the edge where the last swab left the surface.
Of course you can't do this if the lens is covered in lots of particles, especially coarse ones. Careful use of canned air, with the right kind of valve, and applied so as to avoid thermal shock works perfectly well but also takes practice and knowing which canned air, or valve type, to avoid. Brushes are kinda dangerous, I gave up on 'em and only use a lens pen or the like when it really doesn't matter much. OTOH, good quality lens cloths with a good quality lens cleaner (Schneider PhotoClear for instance) works pretty well, almost perfectly if you're not using magnification, but they won't get a lens perfectly clean and _will_ scratch due to particles you can't see, leaving scratches you can't see without magnification either. They also can wear away the coating over time since they work mostly by sc/rubbing the surface clean whereas the acetone method is far less physical.
Hope this makes sense, kinda hard to describe. And I wouldn't even attempt it without knowing exactly what you're doing, just so's you know. I'm not recommending this method, only outlining it. I did use it to clean the optics of a demo Zeiss T* PRF that came in Tuesday and it worked fine until I hit the ranging lens. D'Oh!! Wasn't happy with the acetone. At all. Salvaged it though and it works fine but lots of strong language for a bit.
HTH, Pete
