Emulsion
Ferric
Ammonium Citrate ( green scales ): 2.5 grams
Oxalic Acid :0.4 grams
Silver Nitrate :1.0 grams
Distilled Water to Make: 30 mils
Mix
in listed order. Larger amounts may be made by multiplying quantities
by either 5 or 10. Store solution in a dark brown bottle and allow
to mature, or age, over night.
Application
and Exposure:
Spread
the emulsion - on high quality, acid free, water colour paper
- with a non metallic brush. This is very important as the metal
will react and spoil the solution. Alternately use a Blanchard
applicator.
Dry
the coated paper with a hair dryer on a low setting. Be careful
not to have it on a high setting as this will fog the emulsion.
Exposure
is carried out under a rich Ultra-Violet light source or sunlight.
Exposure is continued until details are visible in the highlights.
Under exposure causes the image to be too pale. Over exposure
causes shadow detail to be lost and the highlights to discolour.
Developer
Borax
: 7 grams
Hot Water to Make : 1 Litre
Develop
in the above solution for 5 minutes. The print will appear too
flat, with some highlight fog and weak shadow detail after development.
Don't worry this is corrected in the fixing stage.
Rinse
the developed print in water for four minutes.
Fixer
Sodium
Thiosulphate : 15 grams
Water
to Make : 1 Litre.
Use
the above formulae to make two fixing baths. Fix for five minutes
or until the highlights are clear. Over fixing will bleach and
reduce the image too much. Though this can be useful for a print
that has been overexposed.
The
colour of the print will darken to a blackish brown in the fixer.
Once this colour change has occurred and the highlights are cleared,
remove from the fixer so as not to bleach the print.
For
greater permanence, the print can be placed in a hypo clearing
solution for about 5 minutes.
The
next stage is to wash the print in running water for a minimum
of 30 minutes, longer if the temperature of the water is low.
The
final stage is to allow the print to dry naturally.
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