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.
Toning. Sometimes prints toned in the combined bath are not permanent. There are also times when some prints of a batch are permanent and others fade quickly. This is generally caused by the printer over-working the combined bath; i. e., he has toned more prints than the quantity of bath will stand. The combined bath contains a certain amount of gold, which will tone a given number of prints. As the gold deposit gives the permanent tone, when this gold is exhausted there then remains only the lead and hypo, which will produce a so-called lead-hypo tone that is not permanent. The bath also contains a limited amount of hypo, sufficient to balance the amount of gold, and will only fix a certain number of prints. Fixing is a dissolving and eliminating of the unchanged silver in the prints, thus making them permanent. Therefore, if more prints are toned and fixed in the bath than the amount of gold and hypo is able to tone and fix, the prints will be neither toned nor fixed, and, consequently, not permanent
382. THE TEMPERATURE should never be higher than 50° Fahr., both winter and summer. If the temperature is higher than 50° you are apt to produce sulphuriza-tion, and sulphurization will cause the prints (although the tone may be pleasing) to fade very rapidly.
383. For the beginner we advise the use of prepared toning powders or solutions. These powders or solutions are generally put up in concentrated strengths, requiring the addition of so much water before use. It is generally best to allow all toning baths to stand for twelve hours, to ripen before using.
384. A good plan is to prepare the bath the day before it is wanted. After the beginner becomes accustomed to the use of the prepared powders he can prepare his own combined toning bath according to the formula given below.
Hyposulphite of Soda............
385. Dissolve the hypo in the 80 ozs. of water first; then add and dissolve the balance of the chemicals, one at a time, in the order they are given. When these are all dissolved add to the above
Borax ............... 2 ozs.
Hot Water ............. 8 ozs.
Chloride of Gold..........
ACetate of LEad (Sugar of Lead)............
THE EFFORT Study No. 7 - See Page 370 By C. F. Clark.
386. Chloride of gold can be purchased in 15-grain tubes. Make of this a liquid stock solution, by placing the chloride of gold in a 16-ounce bottle, adding the acetate of lead, and then dissolving these two chemicals in 15 ozs. of water. This solution will then contain one grain of gold to every ounce of solution.
Note. - Solution B should be shaken up before using, and not filtered.
To tone fifteen cabinets, or their equivalent, take,
Stock Solution A............
Stock Solution B...........
387. An extra fixing bath should be used to insure thorough fixing. After the salt bath, give three changes of cold water, and then fix for ten minutes in the extra fixing bath, composed of
Hyposulphite of Soda............
Sulphite of Soda (Crystals).........
388. Wash one hour in running cold water, or in sixteen changes of cold water, when prints are ready for mounting. The combined bath must be used cold - not over 50° to 55° Fahr. If the bath is too warm it will cause yellow prints, with a greenish cast in the half-tones. The combined bath is an acid solution. The borax neutralises only the excess of acid in the alum. Any attempt to neutralise the bath would precipitate the alum. The combined bath should not be used the second time.
389. As all prints toned in combined bath dry down one shade darker in tone, you must allow for this and remove the print from the bath one shade warmer than you would like the finished print. It is advisable to keep the bath below 55° Fahr. during toning, and when it is not in use keep it in a cool place. In order to keep the bath at the proper temperature, provide yourself with an all-glass dairy or bath thermometer, which is inexpensive, and by keeping it in the bath constantly, while toning, you can regulate the temperature of the bath at all times. If it is impossible to obtain an all-glass thermometer you can use one on an aluminum frame, or even an ordinary thermometer attached to a wooden frame, provided the glass is fastened in without nails or anything of iron, as iron will ruin a toning bath.
390. In summer fill a tray, which should be a few inches larger than the toning tray, with broken ice. In this place the toning tray, which must be of glass, porcelain or enamel lined. (A metal tray would destroy the toning bath, causing it to turn black; the prints would have iron rust spots on the surface, and the bath containing prints would not tone at all.) Pour the toning bath into the tray, place the thermometer in the bath, and when it registers 55° Fahr. you are then ready to commence toning. The warmth of the hands will keep the bath at about 55° Fahr. Should it become too cold, lift the tray from the ice for a few minutes, placing it on a table, and the temperature of the bath will rise very rapidly. It is better to have the bath too cold than too warm.
391. When your prints are made and your bath is ready for toning, in order to avoid spots caused by perspiration rinse your hands in a weak solution of carbonate of soda, after which wash and dry thoroughly. Then place prints for toning on a cardboard box cover (a trifle larger than the prints to tone). Hold this cover in the palm of your left hand and tear off one side of the cover. Then, with the right hand, slide the prints face down, one at a time, into the toning bath, being careful to cover the entire print with the toning solution. (See Illustration No. 54.) When you have in this manner placed one-half dozen prints in the bath, turn them face up, and with the finger tips of your right hand remove the little bubbles or air-bells that may have gathered on the face of the prints. These air-bells, if not removed, will leave black or yellow spots. After removing them, turn the prints face down and place half a ft dozen more prints in the bath. Proceed with these as with the former six, being careful to remove the air-bells. The twelve prints will be enough to handle until you become accustomed to the toning.
392. As the prints lie face down, draw out the bottom print and transfer it to the top, turning it face up. Repeat this operation until each of the prints, in turn, have been brought from the bottom to the top and turned face up. Then start again with the bottom print, transferring it to the top and turning it face down. Keep this up as long as the prints are in the bath, the object being to keep them constantly in motion while toning. By turning them, first face up and then face down, you will always know which print was moved last, and thus make sure that each one receives its proper share of handling. Continue this until the desired tone is obtained, say twenty minutes. If your bath becomes warm the prints will tone much faster, but the tone will not be permanent. Therefore, you must watch and not allow the temperature of the bath to go above 55° Fahr.