The Dictionary Of Photography

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

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Bromide Paper
faults is obvious. The cure of the same, when existent, depends solely upon the nature of the fault. Thus, if the yellow colora-tion be due to a compound of iron it may frequently be removed by using a bath of
Sulphuric acid         ... ... ... ... 25 parts.
Water           ...............500 ,,
or
Neutral oxalate of potash ... ... ... 25 parts.
Oxalic acid ... ... ... ... ... 5 ,,
Sulphuric acid         ... ... .".. ... 5 ,,
Distilled water         ... ... ... ... 500 ,,
The prints should be allowed to soak in either of these baths for about ten minutes, and then thoroughly washed. If the stain is still persistent, it may be assumed to be sulphur deposited in the paper. We have found, however, that many a yellow stain on bromide paper will yield to the following treatment, although it may refuse to budge by treatment with either of the above baths. The print is thoroughly well wetted and laid at the bottom of a dish, with just sufficient water to make it adhere flat to the bottom without floating about. The following powder is then sifted over the print; it may also be applied in the form of a paste. When sifted over the wet print it should form a damp, sticky mass; and this may be allowed to remain on the print for half an hour, and then well washed and dried.
Salt of sorrel, or acid oxalate of potash .... 15 parts.
Cream of tartar ... ... ... ... 5 ,,
Blisters. These pests sometimes make their appearance when using bromide paper, usually in the first washing water after fix-ing, and they may be partially prevented by adding a handful of salt to the first washing water after fixing, or preferably by using the following bath just after clearing : -
Chrome alum           ... ... ... ... 25 parts.
Sulphuric acid          ... ... ... ... 6 ,,
Water            ...............250 ,,
It is absolutely necessary that the print should be well washed to eliminate the alum, or yellow stains would ensue from the decomposition of hypo by the alum, and consequent deposition of sulphur. See Formalin, for another preventive of blisters. It seems almost unnecessary to give any explanatory notes
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