This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
. 16 Ozs.
.. 4 Ozs.
Sulphite of Soda (not Sulphite)...............
.. 8 ozs.
980. The hypo and alum should be dissolved while water is boiling hot, and after it is cool add sulphate of soda. This bath will be milky in appearance, having a white precipitate. It may be used this way, or allowed to settle, pouring off and using the clear portion. A new bath may show a tendency to bleach, and to overcome this it should be ripened with silver. A convenient method of ripening is to put some unused pieces of photographic paper, containing silver, in the bath previous to toning. After the bath ripens it can be used repeatedly until it refuses to tone. It will take from 15 to 30 minutes to tone prints, but they need no particular attention after they are thoroughly and evenly saturated with the bath. If the bath is very cold, or after it becomes old, it will work more slowly. To hasten its action it may be warmed slightly. Never use it at a temperature of more than 90 degrees Fahrenheit, or the action will be too rapid and difficult to control. The toning may be done in daylight. Prints should only be toned far enough to remove the decided olive color. It is advisable to leave a slight trace of olive in the print, as this disappears in drying, leaving a brown black tone. Do not over tone, or the prints will be blue black instead of brown black. After prints are toned, separate well in running wash water and wash for one hour. If running wash water is not available, it will be advisable to put prints back in the fixing bath to check the toning action. Then wash.
Note. If the tone of the print is satisfactory after being fixed, the use of the toning bath may be omitted. The purpose of this bath is to change the olive to a brown black and is NOT a necessary part of the process for those who want the olive black tone. If difficulties arise look under head of "General Information" for suggestions. For instructions in regard to mounting and drying, also consult text under the above head.
Sepia Tones On Iris. Beautiful sepia tones can be obtained upon Iris paper by toning in a toning bath mixed according to the formula given in paragraph No. 979. Iris prints intended to be toned sepia should be made in the ordinary way, and a shade darker. Fully and evenly developed prints give the best tones. It will take from 8 to 12 hours to convert prints to a full sepia, if the bath is used cold. Using the bath at a temperature of 100 degrees Fahrenheit will tone prints in about 30 minutes. Prints need no particular attention, as the toning proceeds to the sepia point and then stops. If a cold bath is used, prints may be allowed to remain in it over night. The only precaution necessary is to stir prints occasionally during the first stages of toning. After they are thoroughly and evenly saturated with the toning bath, they will need no further attention. Prints should be toned face up.