[Leica] PEC-12 = lacquer thinner? [was: to POOF or not ...]

[pieter@world.std.com (Pieter Bras)]

Ron Miller quoted Dan Post:

>For really tough greasy spots, a dab of PEC-12 film emulsion cleaner on
>microfiber has come through for me.  I also use it to get the greasy smudges
>off my glasses, and to clean the eyelash smudges off the eyepiece!  I figured
>that if it will not hurt a delicate photographic emulsion, it won't hurt the
>mineral coating on the lens-it hasn't so far, nor has it affected the
>paint/anodizing, and I've used it for years.  Use sparingly- better to clean
>twice with too little than to use too much!

You've been lucky so far.  Recently I cleaned my Schneider 4X loupe,
which accumulates oil from my eyelashes.  It was late, and instead of
reaching for the bottle of ROR, I grabbed the bottle of PEC-12 next to it.
The mix-up went unnoticed until I noticed a hazy sheen on the lens that
wouldn't come off.  Finally realizing my mistake, I finished the job
with ROR.  However, there are now lots of swirl marks and fine scratches
on the coating of my loupe, and it had survived undamaged many cleanings
with ROR before then.

The PEC-12 bottle doesn't identify its ingredients.  It just says
"For professional photographic use only.  Not to be sold for personal,
household, or family use."  To me, it smells just like lacquer thinner.
As an experiment, I smeared some grease, fingerprints, and Sharpie
"perrmanent" marker on a glossy color print, and both PEC-12 and lacquer
thinner did an equally effective job of cleaning it off.

Maybe Leica coatings are different, but I certainly don't plan to wipe
lacquer thinner, or PEC-12, on any of my optics again.

- --
Pieter Bras