to secure uniform
tones is to slip the bottom print out and place it face up on top of the
others, which should be face down in the tray. As soon as the last print
has been turned in this way, turn the whole batch face down and repeat
the operation. By handling the prints in this manner, the toning process
is seen at once, and as soon as a print has received the desired tone it
can be taken from the tray and placed in a dish of running water.
The prints should wash half an hour or more. The color obtained in the
bath will remain. It does not fade as does the albumen print on being
removed from the toning bath.
The gelatine prints should be toned at once after printing. Even if they
are kept in a perfectly dark place, the half tones and high lights
quickly discolor.
The separate toning baths are easily prepared. What is called the stock
solution is made as follows: 15 grs. chloride gold and sodium, 7-1/2 oz.
of water.
Dissolve and keep in a tightly corked bottle, marked "Gold Solution."
Chloride of gold and sodium comes already prepared in 15
grain-quantities, and costs thirty cents a bottle.
The other stock solution is a saturated solution of bicarbonate of soda.
A saturated solution is a solution which contains a little more of the
substance dissolved in it than it can hold in solution. This is shown by
a deposit on the bottom of the bottle.
To make the toning bath, take 3-1/2 oz. of water in the graduating glass
and add 1/2 oz. of the gold solution. Dip a piece of blue litmus paper
into the solution, and if it does not turn the paper red add a little
more of the gold solution until it does. Then add enough of the
bicarbonate of soda solution till it turns the litmus paper back to
blue. A few drops of the soda solution should be added at a time,
stirring the solution with a glass rod.
Mix the bath half an hour before wanted for use. Place the prints in
this bath without previous washing, and tone till the required color is
obtained. Rinse and place in a fixing bath composed of 1 oz. of
hyposulphite of soda and 8 oz. of water. Leave them in this fixing bath
five minutes, then wash for half an hour in running water.
In preparing stock solutions, label the bottles and write the formula
with direction for use on the label. This saves time and trouble.
In preparing chemical solutions one must be very exact, as a little more
or less of one ingredient sometimes produces chemical changes in the
solution, re
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