From: Michael Healy (mjhealy@kcnet.com)
Date: 11/05/02-03:56:03 PM Z
Hi, Richard. I haven't been doing this for very long myself, so my
experience is limited. But I wonder why you don't just expose one and see
how THAT rinses out? I believe that exposure to UV actually is changing the
chemistry anyhow.
I suggest that you post a specific list of the papers you're using. What
brands? Which models of their brands? What is their g/sm? Are they HP?
Rough? How sized in manufacture?
My experience is limited to post-exposure rinsing. Here, I have had some
trouble clearing one paper: Windsor Newton 140 lb HP. However, most of my
tests did clear very well. So it leads me to suspect
that my rinse time was the problem. (In my original tests of it, I was
rinsing for 5 minutes.) When I rinse for longer, say 10-15 minutes, this
paper does clear fine.
I also have used a number of other papers: Arches Platine, WN 90 lb HP,
Rives BFK, Simili Japon, Coventry white, Fabriano Uno, and Somerset Satin.
These are of various weights and seem to show a range of sizing (that's what
I assume, since they do not all absorb in the same way). So far, none hold
stain in the highlights. Only the WN 140 lb. HP has given me trouble.
So I suspect that one place to look is the combination of your rinse time
and the particular paper (due to its sizing). If a paper has absorbed the
coating relatively better, then I imagine it's going to hold onto the stain
when you try to rinse. Someone else on the list may correct me about this.
Anyhow, I think you should post a list of your papers, and be as specific as
possible. Also, I really do think you ought to just take some of these and
go expose them.
Mike Healy
----- Original Message -----
From: <rurmonas@senet.com.au>
To: <alt-photo-process-l@usask.ca>
Sent: Wednesday, November 06, 2002 1:44 AM
Subject: Problems clearing with cyanotype.
I have not been able to clear (i.e. wash out the yellowish stain)
my cyanotypes on a range of papers. As a test I took a sample of
several papers and used the following procedure:
- Coat paper using a foam brush. This is done under yellow light.
- Dry paper in the dark using a small fan to speed drying
- Wash the paper (mostly in the dark, brief preiods of yellow light)
for 30min in tap water with minimal aggitation.
Note: The paper receives no exposure. I leave a strip uncoated to judge
the clearing effectiveness. All inspection is done after the paper has
dried.
I found a substantial yellow stain remaining on 2 of 6 papers, light
staining
on another 2, and only 2 papers which fully cleared. I am testing good
quality
papers, and papers that I have seen listed as good for cyanotype in the
archives of this list, and on various websites.
My questions are; what an I doing which is resulting in the poor clearing ?
Should I be using some special bath to assist clearing ?
Thank you,
Richard
--- Richard Urmonas rurmonas@senet.com.au ------------------------------------------------- This mail sent through SE Net Webmail http://webmail.senet.com.au
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