The Dictionary Of Photography

A True Historic Record Of The Art & Practice Of Photography 100 Years Ago.

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Bromide Pencils                                                     Bromine
Dr. Stolze also suggests bleaching the image with a solution of bromide of copper, stating that this is preferable to chlorising the image, as stains are less likely to appear. The bromide of copper solution can be made by dissolving: -
A. Copper sulphate ... ... ... ... I part
in
Distilled water ............ ioo parts;
B.
Potassium bromide...... ... .... I part
in
Distilled water............ ioo parts,
and mixing the two solutions ; the thus bromised image should be well washed, and then exposed to daylight and redeveloped with the above eikonogen developer mixed in the following proportions: -
Solution A............... 50 parts,
.. B............... 20 ..
Water            ...............5000 ..
Bromide Pencils. Special pencils for retouching, spotting out and working up bromide prints and enlargements.
Bromides. These are salts formed by the union of bromine with a metal or pseudo-metal. The alkaline bromides, potas-sium and ammonium, are used as restrainers, or for emulsion making. The question often arises as to whether these two are of equal efficiency as restrainers, but has not been satisfactorily answered. If Abney's view of their action be accepted, then the ammonium salt should be the stronger. He says: "In the formulae with pyrogallic acid, it will be noticed that a soluble bromide is recommended to be added to the solution of pyro-gallic acid and ammonia. This is to check the reduction of the unaltered silver bromide, the soluble bromide seemingly forming a compound with it, which is much less attackable by the developer."
Bromine (Ger., Brom; Fr., Brome; Ital., Bromd). Br = 80. A non-metallic element obtained as a deep orange-red liquid from sea-water. It is used to form the bromides.
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