OK !
I won't touch it ! by any meaning.
I will wait till new advices.
Sincerely.
Ezio
www.lucenti.com e-photography site
----- Original Message -----
From: "Michael Moore" <miguelmas@qwest.net>
To: <filmscanners@halftone.co.uk>
Sent: Tuesday, March 20, 2001 3:31 AM
Subject: Re: filmscanners: cleaning neg's, sharpening
> Ezio : In case you missed my earlier posts.... DO NOT TOUCH THAT
EMULSION... it
> was made and developed long before hardening fixers were used... the
compressed
> air could blow it off the plate, the cotton will almost certainly scrape
it.. if
> you feel you must, try your cleaning on a plate that you can aford to
lose...
> This from my earlier post....
>
> Ezio: I just did a little checking on Google the search engine
(www.google.com)
> under the term "glass plate photographic preservation". I got a lot of
> references... this is one of them that sums up what most of the other say
in
> regard to storage and
> handling....
>
>
>
> Ezio wrote:
>
> > Oh ! Friends ... I am Italian !!!! and thus my family and myself ...
> > everybody is drinking carbonated water either industrial either home
made
> > (I've got all the equipements to inject CO2).
> > I have also a micron filter carbon filter active ... to remove all the
stuff
> > provided by the public water agencies i.e. clorine, atrazine, ddt etc.
etc.
> > etc. the water in my house is treated through system to remove any
> > particular part of CaCO (Carbonated Calcium) producing those white rocks
> > inside the pipes and inside some kidneys ...
> >
> > I was thinking to use truly distilled water and demineralized.
> >
> > Then I saw many doubts rising ... following your advices and I am
thinking
> > to use compressed air and very soft material (cotton) only .
> >
> > I am scared to see the emulsion/gelatine melting down under the action
of
> > water ...
> >
> > Sincerely.
> >
> > Ezio
> >
> > www.lucenti.com e-photography site
> >
> > ----- Original Message -----
> > From: "Arthur Entlich" <artistic@ampsc.com>
> > To: <filmscanners@halftone.co.uk>
> > Sent: Monday, March 19, 2001 8:51 AM
> > Subject: Re: filmscanners: cleaning neg's, sharpening
> >
> > >
> > >
> > > Mark Thomas wrote:
> > >
> > > > Just a couple of quick comments..
> > > >
> > > > 1. Cleaning neg's with water
> > > > Bear in mind that if you use anything but 'unexposed' distilled
water as
> > > > a cleaning agent, you are in fact using carbonic acid..!
> > > > I used to work in a oceanographic lab, and while checking the pH
levels
> > > > of a distilled water producer, I was surprised to discover how
acidic
> > > > the 'pure' water was. The resident chemist gently explained that
H20,
> > > > when exposed to air, absorbs CO2 and degrades quite quickly to a
> > > > carbonic acid solution, of about pH 5.0-5.5 I think. (I'm flying by
> > > > memory here - any chemists on the list feel free to correct..)
> > > >
> > > > Keep that in mind if considering water for cleaning fragile items!!
> > > >
> > >
> > > Well, I think he was giving you a bit of a jest. As you probably
know,
> > > water is supposed to be neutral, or pH 7. Drinking water, at least
here
> > > in Canada, cannot be beyond pH 6.5 (it can go alkaline to 8.5).
> > > Although it is true that water does absorb minimal amounts of CO2, the
> > > pH is not likely to vary much, and the amount of acidity is minimal.
> > > However, if you live in an area with severe acid rains, it could get
as
> > > acidic as a tomato, but this is due to the rain going through sulfur
> > > dioxide and becoming sulfuric acid when the rain goes through it. If
> > > your water to begin with is fairly neutral, the amount of CO2
absorption
> > > to standing water will not do much... if it did, most fish could not
> > > survive in it. Soda pop is created by bubbling CO2 through cold water
> > > and it has to be kept under pressure in order to keep it there.
> > >
> > > Art
> > >
>
