Fw: How to super harden papers?

From: John Cremati ^lt;johnjohnc@core.com>
Date: 03/28/05-03:56:06 PM Z
Message-id: <000a01c533e0$f1a2db00$19a551d1@k1t0l0>

          A while ago I was fortunate enough to see several actual Fresson
Prints that Art Chakalis had....... The base coating or sizing of the
paper seemed quite unique........ .............It appeared almost like a
white opaque gesso coating as you would see on a artist canvas yet a much
finer surface............Art even felt it was a significant part of the
Fresson secret process.

John Cremati.....

----- Original Message -----
From: "John Cremati" <johnjohnc@core.com>
To: <alt-photo-process-l@skyway.usask.ca>
Sent: Saturday, March 26, 2005 4:19 PM
Subject: Re: How to super harden papers?

> Hi Rich,
> I got all my information out of " Photographic Emulsions for
> Idiots"
> The doubt if the info would be wrong!..
> John
> ----- Original Message -----
> From: "Richard Knoppow" <dickburk@ix.netcom.com>
> To: <alt-photo-process-l@skyway.usask.ca>
> Sent: Saturday, March 26, 2005 2:54 PM
> Subject: Re: How to super harden papers?
>
>
> >
> > ----- Original Message -----
> > From: "John Cremati" <johnjohnc@core.com>
> > To: <alt-photo-process-l@sask.usask.ca>
> > Sent: Saturday, March 26, 2005 3:59 AM
> > Subject: Re: How to super harden papers?
> >
> >
> > > Hi Sandy,
> > > Just some thoughts.
> > > I know with my little experience in extreme high
> > > relief , the ph
> > > is said to be the critical factor in the amount of
> > > swelling the gelatin is
> > > able to do.....The maximum swelling is achieved about a PH
> > > of 8.4 with the
> > > minimum swelling taking place at about 4.7....... As a
> > > thought, maybe you
> > > are coating or attempting to size the paper at or close
> > > to a maximum
> > > condition in the wet state...... Then when dried, it has
> > > not sized the paper
> > > sufficiently .....
> > > Possibility the paper reacts with the gelatin
> > > causing the ph to be
> > > changed at surface level and again when dry, it does not
> > > have the amount
> > > of gelatin size necessary to do its job.................
> > > Another thought is the pigmented emulsion at a ph
> > > of 8.7 causing
> > > high relief in the wet state but low relief when
> > > dried.....Maybe as a
> > > experiment I would try coating the paper using a PH
> > > emulsion opposite of
> > > what you are using to see what you may see .
> > > Please let me know of your progress.
> > >
> > > John Cremati
> > >
> > Are you sure that maximum swelling occurs at pH 8.4? It
> > seems to me that swelling continues to increase on either
> > side of the isoelectric point of the gelatin. Also, pH 4.7
> > seems to me rather too low for photographic gelatin as found
> > in printing paper although it might be right for the gelatin
> > used to make carbon tissue.
> >
> > ---
> > Richard Knoppow
> > Los Angeles, CA, USA
> > dickburk@ix.netcom.com
> >
> >
> >
> >
> > _____________________________________________________
> > This message scanned for viruses by CoreComm
> >
>
Received on Mon Mar 28 15:52:28 2005

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