421. Bromide Of Potassium

Bromide Of Potassium. Bromide of potassium is a white crystal used as a restraining agent. It restrains the development and holds the shadows clear throughout the developing.

422. Altering Developer

Altering Developer. While this developer can be altered to produce any desired effect, yet it is advisable to develop for some time with the regular formula as given until you become thoroughly familiar with the results to be produced. If after having some experience you find the developer working a little contrasty, you can produce more softness by reducing the amount of hydroquinone. For instance, instead of using forty grains of hydroquinone use thirty-five, and if this does not give you the desired softness, then increase the eikonogen to 130 grains. Care must be exercised that you do not use too much of the eikonogen, as it is apt to produce fog. In case of too much softness with the regular formula, increase the hydroquinone to forty - five grains, and if still too soft and a lack of contrast, increase to fifty grains. Just remember that hydroquinone will give you contrast, and eikonogen softness, so you can alter your developer to produce whatever results you desire. Both chemicals being powerful, the alteration should be made with but a few additional grains at a time, and a small quantity of stock solution should be prepared to experiment with. When you once obtain a well-balanced developer, do not alter it, for too much altering usually causes confusion, and leads to many failures. The formula as given will give you a well-balanced developer for all ordinary purposes, and unless the results are very much out of the way, it is not advisable to alter the proportion, but use the developer according to formula, and in case of too much harshness, indicating under-exposure, manipulate the developer with Special Stock Solution No. 3, made as follows: -



........10 ounces


........120 grains

This solution must be kept in a bottle and the bottle well wrapped and with good stopper. In case of too much contrast, harshness, remove the plate from the normal bath, and add from ten to twenty drops of No. 3. Mix well, and return the plate to this developer, and conclude the developing in this bath. Eikonogen is a detail-producing chemical as well as developing agent, and by increasing the amount of this chemical within the limit to avoid fog, usually an under-timed plate would be very much improved, and a good negative will result.

424. If you find the plate you are developing is overexposed treat according to instructions on developing overexposures, and either add a few drops of ten per cent, solution of bromide to every ounce of developer you use, or transfer to old developer, which of course contains bromide liberated from the plates which were previously developed in this developer. If extremely over-exposed, soak in the bromide solution before developing. Follow instructions given in developing over-exposures with pyro developer.

425. Incases of extreme under-exposure after the plate has started to develop, and the image appears contrasty and weak in the shadows, place the plate in a tray of fresh water. In the meantime add to the bath one ounce of No. 2, two ounces of water, and a few drops of bromide. The bromide will prevent the fog and give the eikonogen and accelerators a chance to act on the shadows. Complete the developing in this bath. By means of Special Stock Solution No. 3, and the bromide solution you have absolute control of plates under all conditions, and by working carefully and using judgment any desired result can be obtained. All stock solutions must be kept in tightly corked bottles, glass stoppers preferred. Have the bottles brown or yellow. If plain glass bottles are used, wrap with dark paper, and place them in a dark, cool place in the dark room.