Re: Cyanotype printing
Bruce McCaughey (dcav@unixg.ubc.ca)
Wed, 13 Mar 1996 08:55:29 -0800
> I have in the past used a dilution of 25cc 37% hydrochloric acid to
>1litre of water to heighten the blues in my cyanotype prints.
> I am curious to know if there exist weaker concentrations of
>hydrochloric acid.
> I am also curious to hear of experiences anyone call tell me of
>using hydrochloric acid versus a dilution of hydrogen peroxide or bleach in
>cyanotype printing. Anybody???
>
>thank you
Hi Risa
It sounds like you are using 3% solution of hydrochloric acid which
I tried and got almost no effect. Could I have done something wrong, some
one else mixed the chemicals? As I recall the hydrochloric acid was
supposed to produce a green tone but nothing happened and I didn't
investigate further.
I now use a 10 % solution of potassium dichromate which produces
what I would call a navy blue colour( this is on hand made paper). The
effect happens very quickly (30 seconds) and adds contrast to the print. If
you are getting results with the hydrochloric acid than I will try again. I
would be interested in any other methods that people use to produce other
tone. I have used tannic acid but the brown tone was not what I was
looking for.
T/\/\/\/\/\|| Bruce McCaughey
|| ||---| dcav@unixg.ubc.ca
|| ||---| Vancouver, Canada
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