The principle of the salted print is very simple. Two elements need
to come into contact while being exposed to ultraviolet (UV) light; salt
and silver. That creates the black left on the paper after exposure.
Bringing those two elements together on paper to create a finished image
is not an absolute or fixed method. There is a fair amount of
accommodation available to compensate for the density range of the
negative, by altering the two constituent elements respectively. As I
have noted in earlier posts, the density range of a negative, beyond
being "thin" or "thick", is measured using the D Log E curve
densitometric notations; Log E 1.2 to 1.8 densities respectively for
printing in most hand coated methods. I will explain the concept of D
Log E, as well as the related procedures of expansion and compaction
in a following post for a better understanding of this concept. For
now, it is assumed the photographer has a negative with sufficient
densities to print in hand coated silver.
Salted Paper "Binder";
Sodium Chloride ~ Table Salt (try to use unprocessed salt) I use Sea Salt
Silver Solution;
Silver Nitrate; (crystals)
Mixture ratios for negative densities;
For negatives that have a density range of Log E 1.2 - 1.8 (preferred density range)
Salt ~ 2% - 3%
Silver ~ 12% solution
For negatives with a density range below Log E 1.2 (thinner negatives)
Salt ~ 1% - 1 1/2%
Silver ~ 10% solution
The
above mixture ratios are standard issue from most sources available
today. Just know they are just that, standard applications from which
one begins from. As I have posited many times, black and white
photography is very malleable, and can be applied in many various ways.
The relationship to take away from the above ratios is simply that
thicker negatives require increased portions of both salt & silver.
By substituting the amount of salt solution percentage as well as silver
solution, it is possible to accommodate a range of negative densities.
Testing of course is very desirable.
My silver/salt printing ratio for the images I've been posting.
Silver Nitrate ~ 13% solution (saturated solution)
Salt (table salt) ~ 2 1/2% solution
Paper Preparations; (My formula)
Water (at 120 degrees) 1000 ml
Salt (2 1/2% solution) 25 g
After
pouring the salted water into a developing tray, slip the printing
paper into the tray and agitate enough to keep the paper from laying
flat on the bottom of the tray. Soak the paper for at least thirty
seconds, making sure all areas are evenly soaked, then hang to dry. I
used a length of twine hung above the sink and wooden clothes pins
strung along the twine for pinning and hanging the paper after soaking.
That's it. Paper that has been salted can be stored in a dark, dry area
for a good length of time without deterioration.
Application of Silver;
I
used the above formula of salt with a silver solution of 13%, which is a
saturated solution of silver. I always double coated my prints with the
silver solution, drying the first coating before applying a second
coat. My reasoning for this was simple. The old silver saturated papers
of the past were so much more richer than the newer papers. More silver,
saturated deeper into the paper, should, theoretically return a richer
print with deeper blacks, leaving a print with more visual depth and
texture. From my experience, that position was vindicated after
comparing a one coat print with a two coated print.
Once
the paper that has been coated with the silver solution it can be
stored in a dark dry place as well, for awhile. I use old printing paper
boxes for storing my treated paper, well marked to keep the different
papers separated. Personally speaking, I do not store a silver coated
paper. I print as soon as it is properly dried. The pre-salted sheets of
paper can be kept in a printing paper box for a week or more, ready for
applying the silver when needed, without any deleterious effects.
When
I began printing hand coated silver, I had only the sun as my UV
source. That takes a bit of experimentation to realize a printing time,
according to a "sky choice". I used the north light method, keeping the
printing frame in north light shade, aiming the print towards open blue
sky, away from direct sunlight. That will be about as constant as once
can get using sunlight. It is very important to meter the sky you will
be using and noting the intensity, usually in lumens, to keep tract of
printing time. This is important.
There is a
relationship between light intensity and print contrast. The lower the
light intensity and longer the printing time, the more contrasty the
final print. With caveats. Hence, if the print is faced into the direct
sunlight, the printing is much more rapid, affecting the high density
ranges far more quickly than when in low light, thereby tending to
'flatten' the image more. Using the north light, lower intensity input
tends to lengthen the tonal range of the print as it prints in much
slower. This relationship allows the printer to use either, or both
methods combined, to control the printing process further. If the
negative is very dense at the upper end, one can print in much of the
print using north light, then turn it to full sun for a minute or so to
burn in the upper tonal range, usually Zone 7-8. Reciprocally, if a
thinner negative is used, one can use strictly north light only to
increase the final tonal range to the maximum amount for that negative.
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