RE: Cyanotype - brown stain.

I experienced persistent problems with staining in the non-image parts
of cyanotype until I started rinsing them in warm rather than cold
water.
Do you wash under running water Pawel? You need to start with a warm
fast running wash diectly on the image surface (under a tap or hose)
until no chemistry runs off the surface, then transfer to a slow wash to
clear the remaining chemistry..
Cheers
Kate

-----Original Message-----
From: Loris Medici [mailto:loris_medici@mynet.com]
Sent: Tuesday, 23 August 2005 12:54 a.m.
To: alt-photo-process-l@sask.usask.ca
Subject: RE: Cyanotype - brown stain.

Hi Pawel,

Which Cyanotype formula are you using (classic or new)? What paper
you're printing on? What kind of water do you use for the
development/wash?

I never experienced brown stains with either cyanotype sensitizers. Just
slight yellowish cast in the highlights - which AFAIK, is caused by
alkali wash water forming an unsoluble compound. The only way I know to
form a brown cyanotype is bleaching it first in ammonia (or another
alkali) and then treating it in tannic acid. If your problem is
yellowish highlight stain then you can try to add 1 dessert spoon of
citric acid into 2 - 4 lt of plain tap water (in order to neutralize the
alkali content of water without making it too acidic - because it lowers
the contrast of the emulsion when it is so) and see what happens.

Regards,
Loris.

-----Original Message-----
From: pawel gega. [mailto:kermit-q@o2.pl]
Sent: 22 Ağustos 2005 Pazartesi 13:35
To: ALT PHOTO
Subject: Cyanotype - brown stain.

hello,

I think it's quite easy for You:

How to counteract neutralize stains on Cyyanotype (after development)..i
it could be neutralized.

How prevent it?

regards,
Pawel Gega

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