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The Barnet Book of Photography A Collection of Practical Articles

Solution of potassium bromide which will act as a restrainer


_Development of Prints._--All my remarks in this article apply equally to most commercial brands of bromide paper; but it is only fair to state that they are particularly intended for that made by the firm of manufacturers publishing this book. Development, and so on, is very similar with all makes of paper, but most of my recent experiments have been made on the "Barnet" matt surface bromide.

I shall presently describe the use of several well-known developers, but it must be well understood that, whatever formula is adopted, a preliminary soaking of the print before development must be done.

When we are about to develop a number of prints we must first soak them in plain cold water until quite flaccid, otherwise the application of the developer would cause the dry print to cockle and curl, and the development would not be regular. This rule applies equally in the case of one print only as when a hundred are ready for development; a prolonged soaking in plain water having no ill effect.

_The Iron Developer._--This is one of the developers most frequently recommended for bromide work, but personally I never advise its use (especially by a novice) because the use of the acid clearing bath, which is an essential part of the process, is so frequent a cause of disaster and yellow prints. The Barnet formula is as follows:--

A. Potassium oxalate 1 lb. Potassium bromide 5 grains Hot water 48 ozs.

B. Iron sulphate 1 lb. Citric acid 4 drams. Hot water 32 ozs.

To six ounces of A, add one ounce of B; this order of mixing must be observed or a dense precipitate of ferrous oxalate will be formed.

Place one of the soaked prints face (which may be distinguished by its "slippery" surface) upwards in a clean porcelain dish and pour the developer over it as evenly as possible. With this developer, the image comes up very rapidly, so that it is not advisable to try and develop more than one at a time. If the first print of a batch appears to be over-exposed, that is, if it flashes out instantly and the high-lights become rapidly clouded, add to each ounce of mixed developer from 10 to 30 drops of a ten per cent. solution of potassium bromide which will act as a restrainer, retard development, and keep the high-lights clear while the shadows acquire density. Under-exposed prints can rarely be made to give passable results with ferrous oxalate. The addition of a trace of hypo to the developer has been recommended for bringing up their detail, but the result is far from good.

As soon as development is complete the prints must _not_ be put in clean water, but must be transferred direct from the developer to the following acid bath:--

Acetic acid 1 dram Water 32 ounces

After an immersion of one minute, the operation must be twice repeated in similar baths that have not been previously used; this is to remove the iron from the print. A thorough washing must next be given to remove the acid and the print may then be fixed for at least fifteen minutes in


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