re: Re: Waterquality for dichromate sensitizers
Dimitri.DUSSART@is.belgacom.be
Mon, 27 Nov 95 15:42:30 CET
tys@masadm1.mas.eurocontrol.be (Henk Thijs) Wrote:
|
| Received: by PI2503670.BC; Mon, 27 Nov 95 15:20:09 CET
| Received: from conch.vast.unsw.edu.au by sugar.h.belgacom.be;
| (5.65/1.1.8.2/24Nov94-1204PM)
| id AA31194; Mon, 27 Nov 1995 15:19:33 +0100
| Received: from (localhost) by conch.vast.unsw.edu.au with SMTP id AA10679
| (5.65c/IDA-1.4.4 for <dimitri.dussart@is.belgacom.be>); Tue, 28 Nov 1995
| 01:16:05 +1100
| Date: Tue, 28 Nov 1995 01:16:05 +1100
| Message-Id: <9511271415.AA20679@masadm1.mas.eurocontrol.be>
| Errors-To: stevea@vast.unsw.edu.au
| Reply-To: alt-photo-process@vast.unsw.edu.au
| Originator: alt-photo-process@vast.unsw.edu.au
| Sender: alt-photo-process@vast.unsw.edu.au
| Precedence: bulk
| From: tys@masadm1.mas.eurocontrol.be (Henk Thijs)
| To: Multiple recipients of list <alt-photo-process@vast.unsw.edu.au>
| Subject: Re: Waterquality for dichromate sensitizers
| X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
| X-Comment: Alternative Photographic Processes mailing list
|
|
| Stefan wrote:
| >..In most photographic processes hard water gives little trouble...
| >..In gelatin-bichromate chemistry, however, it is a peril. Firstly
| >the swelling power of gelatin is reduced; secondly it affects dichromate
| >solutions adversely. It was noticed long ago that a bromoil bleacher made
| >up with hard water seemed to lose power after a week or so, with some
effects
| >on the shadows apparently due to slow interaction between the calcium and
| >chromate ions giving rise to general tanning.
| >Also, in the carbro process, hard water in the sensitizer has the
| >immediately visible effect of eroding the highlights....
| In the bromoil literature I found several times the remark concerning hard
| water. The danger for contamination and unpredictable results is very high
for
| bleachers a.s.o. , so the advice would be to use distilled water; for the
| soaking afterwards put a teaspoon of CALGON into the water
| greetings henk
|
|
I don't think pure water (H2O) will work!
I think the best way to get proper water is to use a water softener / particle
filter from CULLIGHAN.
I've one in my labo, and I can freely attest that I see a big difference when
its connected or not.
I have even seen a progress in classical dev./printing. I do not have to use
products like AGEPON or CALGON anymore.
Hi,
Dim.