Re: Scopes dripping wet

In your refractors. When dew form in the back surface of the lens inside
the tube. After numerous times. Don't you notice any stains? I thought
when water evaporate, it should leave some stains on the glass surface.
In the case of the uncoated FC, there is no way to wipe it because
fluorite being soft can leave wipe marks or fingerprints (well, i wonder
if there is any Tak lover who purposely seek the designer of Tak and has
his fingerprint at the rear as autograph :) ).
Mango
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Mango, No I never had that happen as you describe to any scope I've
ever owned.

Can fogging-condensation on the inside (or outside lens surface for that
matter) leave a stain? Yes it can.

If it is dried shortly after it formed, the stain, or marks it may leave
should not harm a coating.

If the moisture is left for a longer period of time, which may be an
indterminable amount of time, depending on different factors,
temperature, humidity-moisture amount, and the optimal envoirnment for
Mold, and Mildew to grow (I'm not a lab technician, so I can't quote you
precise figures), a permanent problem, or non-removeable etching-damage
to the Coatings, and/or Glass could maybe take place in a day, or two,
or three.

I'm no authority on Takahashi Refractors, as I never personally owned
one (Nor any other scope with Flourite Lenses).

I seem to remember mention though (Probably from Roland Christen a long
time ago), of how uncoated Flourite lenes have a unique property of what
I believe is called "Hydroscopic", in that they can absorb
water-moisture.

Some one please correct me if I'm wrong about this, as I dislike
mis-information about Optics, especially when it's coming from my own
mouth/fingers! :-)
Mark

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