more on Opticlean

[Jack Campin <jack@purr.demon.co.uk>]

A few more comments on Opticlean, since it seems that people who haven't
used it yet don't know what they're missing...

It's safe on every coating I've tried it with, including some very old ones.
It's a variant of a film used for cleaning front-silvered astrotelescope
mirrors, so you'd expect it to be.  I've cleaned dozens of lenses and
filters with it ever since it first came out, and I wouldn't even think of
using tissue, cloth or chamois again - way too dangerous.

You will sometimes get little tags of it left behind on the glass.  When
this happens, just apply a thicker layer and use it to pull itself off.

What it really excels at is degungeing utterly filthy lenses that have been
gathering dust in an attic.  It may take several applications to get it all
off, but nothing else will do this safely unless maybe ultrasonic cleaning.

There are some tricks you can employ with this stuff.  Like, if you have a
lens that only sees infrequent use, you can keep a layer of Opticlean on it
while in storage and peel it off when you need it.  Or you can use it for
painting soft-focus patterns on the front of a lens.

I wouldn't use it on a plastic surface; the solvent smells like amyl acetate.

I suspect there may be cheaper sources for similar substances, like an
astronomy supply house.  They don't give you enough of the sticky pull tabs
with each bottle, but any sticky label will do.

While writing this, I reminded myself what it's like by using it to clean
a Dagor from 1911 that I got in a junk shop for 50 pence a few days ago;
it now looks like it just came off the assembly bench.


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jack@purr.demon.co.uk  -  Jack Campin, 2 Haddington Place, Edinburgh EH7 4AE