Everyone knows or should know the advantage of a properly developed pyro negative. The pyro color, if regulated to suit the printing medium, makes it possible to secure a quality of print that represents the best result the negative can be made to produce.

Occasionally, however, in warm weather when the pyro developer has become too badly oxidized to produce negatives of the proper color for the best results or when an old negative is resurrected for a duplicate order, the negative is found to have entirely too much color for best results on a devel-oping-out paper. The removal of at least a part of the excess of color is a decided advantage in such cases, especially when a number of prints are to be made and the time of printing is an important factor or when the stain of the negative affects its contrast to such an extent that a soft print cannot be secured on the grade of paper which is to be used.

To remove all or a part of the color of such a negative or to remove any developer slain without in any way affecting the metallic silver deposit which makes up the negative image, is a simple matter, though this method has not been generally used.

The process merely involves the bleaching of the negative and redeveloping in a pyro or non-staining developer in daylight and is in no way complicated. A trial can be made on an old negative, only a few minutes being required for the entire operation, and when the necessity arises a negative may be cleared of any developer stain and redeveloped to the desired color for quick, clean printing.

If an old negative is to be freed from stain, first remove any varnish that has been placed on the negative for retouching. Then bleach in the following solution until all the silver image is white.


Potassium Permanganate . 30 grains

Sulphuric Acid C. P. ... 3 drams

Water........ 32 ounces


Sodium Chloride (salt) . . ΒΌ ounce Water........20 ounces.

For use take six ounces of A and two ounces of B. When the negative image has been bleached white the gelatine will have a permanganate stain. Rinse the negative thoroughly and place in a 1% solution of Sodium Bisulphite which will clear it of the stain. Rinse the negative again and redevelop in any developer you may desire to use, but development must be carried on in a fairly bright light, as the image in its bleached condition must be acted upon by light before it will again develop.

The explanation of the process is quite simple. The permanganate and acid acts as a reducer in dissolving the metallic silver, but in the presence of sodium chloride the dissolved metallic silver is immediately transformed into silver chloride and remains in the gelatine, which accounts for the fact that none of the delicate detail of the negative is lost by the process. The silver chloride must be acted upon by light before it can again be reduced to metallic silver, so it is necessary to develop the bleached image in daylight. The process will be found very valuable for removing any developer stain, if it is known that the stain is due to the action of the developer, and the process will be found extremely simple.

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The folks at home want your photograph, in uniform, to be sure, but they may need reminding that you want photographs of them as well.

If you will do the reminding we will make photographs that will please you.

The Pyro Studio Line cut No. 242. Price, 50 cents.

From An Artura Iris Print By E. L. Mix New York.

From An Artura Iris Print By E. L. Mix New York.