Peter Marshall (petermarshall@cix.co.uk)
Wed, 24 Mar 1999 00:24 +0000 (GMT)
>
> Ok, am I right. Is the Ag in the juice the manly way to go? Tell me, I
> can take it, I've been wrong before.
>
> --Dick
Manly I wouldn't know. Over here I think the manly types do it with a
Hassleblad and hand the film in to the lab while they have better things
to do in the dark. More of the wimp myself really:-)
I think it works quite well - I have some nice little warm brown prints
that everyone I give them to thinks are Pt/Pd though I actually think they
have a little higher DMax than I would have got from this. I did some work
with platinum printing using a similar technique - which cut down the cost
of prints, but they never looked as good as the kallitype!
This is taken - with minor changes - from the article by James Thomson in
The Photo-Miniature, Vol. VI Dec 1904, No. 69 ; amounts have been
converted into metric units. The instructions have been rewritten for
clarity. Like all such formulae, it should be regarded as a starting point
for experimentation rather than a stone tablet. The copper(II) chloride
was probably intended to remove any iron(II) present as an impurity in the
ferric oxalate and may probably be omitted without loss of quality,
although it may also form some copper(I) oxide as a part of the image. I
don't know how this may affect the long-term stability.
water 14 ml
ferric ammonium citrate 1.67 g (I used the green salt, although Thomson
probably used the brown.)
ferric oxalate 1.0 g (or solution - cut down on the water)
copper(II) chloride 0.54 g
potassium oxalate 2.21 g
gum arabic 0.67 g (I don't think this is necessary)
Then add a solution of silver nitrate (1.0g) in 15 ml distilled water,
followed by 1.0 g of oxalic acid.
Leave in darkness for 24 hours. Stir well and then filter through cotton
or glass wool to remove only any gritty particles (the yellow heavy
sediment is necessary to the process.)
Coat the paper with the suspension using a brush, wetting the sheet as
quickly as possible without leaving any pools. Allow to surface dry, then
use low heat (30-40°C) to complete drying. For smooth hard surfaces you
may need to apply a second coat . (Adding Tween 20 might be worth
investigating in these cases.)
Expose until only the deepest shadows are visible and immerse face down in
the developer, turning over immediately to see that there are no air
bubbles.
There are various developer formulae around. This is one of several I used
succesfully.
DEVELOPER STOCK SOLUTION
Water 100 ml
silver nitrate 9.25 g
citric acid 2.32 g
di-sodium orthophosphate 0.46 g
(Na2HPO4 - 12H2O may be listed simply as sodium phosphate or as dibasic
sodium phosphate. The equivalent potassium compound may also be used -
half the mass will be needed.)
For working solution, add 13ml of this solution and about 0.2 g of oxalic
acid (for blue-black tones, increasing this goes towards brown-black) to
100ml water. The stock and working solution should be stored in brown
bottles. Both keep reasonably well.
Development should be complete in about a minute but may be continued
longer if needed.
Rinse for a minute or two in clean water (avoid alkaline water - tap water
may need to be made neutral or slightly acid by the addition of a very
small pinch of citric acid.) and then 'fix' for a few minutes in very weak
plain hypo (3 to 4 g in a litre). I then washed in weak citric acid,
followed by a while in running water.
Peter Marshall
On Fixing Shadows and elsewhere:
http://www.people.virginia.edu/~ds8s
Family Pictures, German Indications, London demonstrations &
The Buildings of London etc: http://www.spelthorne.ac.uk/pm/
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