Carbon black was and still is the best lens cleaning substance ever used. Carbon black
(ultra fine powder) acts like activated charcoal and a mild abrasive that is way too
soft
to hurt the coatings but will loosen and absorb almost any gook. It will lift oils and
other stains that you can't get out with other cleaning methods. Often you may see a
lens
with "cleaning scratches", and just as often these stubborn marks are not scratches at
all, but a hard, almost irremovable residue (hard water? dried spit?). Carbon black
has no
binders or adhesives and is not itself sticky, so it can't really fill scratches except
very temporarily (the carbon will blow off). Any commercial compound that claims to
fill
scratches must have a binder and is therefore not pure carbon black. Folks stopped
using
carbon black not because it wasn't the best, but because of the consequences of the
smallest of accidents when using it - not to your lens, to you, your clothing and
anything
surrounding you. Use this stuff outdoors, or be prepared to suffer the wrath of your
wife
if you spill even the smallest bit of it.
The most reliable source of pure, useful carbon black is calligraphy shops where it is
sold (usually as lamp black or bone black) to folks who make their own inks. This is
what
I use to clean my lenses.
The active ingredient in lens pens is carbon.
Regards,
Bob...
-------------------------------
"In the carboniferous epoch
we were promised perpetual peace.
They swore if we gave up our weapons
that the wars of the tribes would cease.
But when we disarmed they sold us,
and delivered us, bound, to our foe.
And the gods of the copybook headings said,
'Stick to the devil you know.' "
--Rudyard Kipling
From: "Provencher, Paul M." <[EMAIL PROTECTED]>
> It is carbon black, used to fill scratches and thereby eliminate unwanted
> refraction from them, improving results with a scratched lens - a very old
> trick, apparently resurrected in new form ("Productized")
>
> I have seen the advertisement - it makes claims way beyond what filling
> scratches with carbon black will accomplish, but in the case of a stray nick
> or scratch, like the one on the lens here:
> http://whitemetal.com/pentax/st_135_25/st_135_25_13.htm
> it can work very well.
>
> From: Lewis, Gerald [mailto:[EMAIL PROTECTED]]
>
> Recently on the tele there has been an advert about a penlike device for
> repairing scratched spectacle lenses. During the demo it shows rubbing on a
> blackish grey substance and then polishing it away to hide the scratches. I
> have no idea if this really works, but might it be the same substance as the
> LENSPEN?
>
> From: Jan van Wijk [mailto:[EMAIL PROTECTED]]
>
> On Thu, 19 Apr 2001 08:39:40 -0400, W Keith Mosier wrote:
>
> >Also, about the lens pen that Tom and many others have mentioned. I've yet
> >to find one in the local stores. What exactly is it? What manufacturer?
>
> Make or manufacturer is "CARSON", name is simply "LENSPEN"
>
> It is shaped like a thick balpoint, with a retractable soft brush on one
> end,
> and under a protective hood on the other end a special shaped foam
> brush, with wat seems to be some very fine black powder ...
>
> >What's it contain?
> >
>
> Maybe something based on carbon-black ???
>
> >I think on the old list several people talked about using carbon black (?)
> >to clean lenses. Is that right?
>
> I think it is, maybe it's in the pen as well :-)
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