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THE PHOTO-MINIATURE and this should, therefore, be used with intelligent caution in connection with paramidophenol developers. In many formulas using metol, the amount of potassium bromide equals the amount of metol. With paramidophenol the proportion should rarely exceed I part of potassium bromide to xo parts of paramidophenol. Generally a less quantity of bromide can be used to advantage. Always, if the paramidophenol is pure, the proportions given will be sufficient to clear the whites. It should also be noted that to secure As to Soclaa the largest efficiency of results with paramidophenol salts, the quality and uniformity of the sodas used is important. There is so much confusion here in commercial brands that the only right way is to use those specifically mentioned in the formula employed, or to select a reliable brand and use that brand uniformly and exclusively. Finally, we come to the complaint that many fail to get sufficient density with paramidophenol to give good printing negatives. This is generally due to the fiact that, with paramidophenol, as with metol and amidol, the image appears rapidly but gains density slowly. Also a little density is lost in fixing. The remedy is obvious. Carry development a little further than seems necessary by the usual visual test, in order to make sure of a negative of sufficient density to yield good gradations in your prints. When paramidophenol-hydrochloride Formula• was first introduced as a negative developer, it was used alone, with sulphite only or with sulphite and potassium or sodium carbonates. Today, however, it is universally used in combination with hydroquinone (replacing the familiar M-Q combination) for plates, films, and papers, so that there is little need to republish the early formulas. I therefore give only a few typical formulas for paramidophenol combined with hydroquinone. For Velox, Azo, and bromide papers ~~~~ as used in commercial work, the following formula is advised. Dissolve the chemicals in the order here given: Water, 32 ounces;

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Modern Photographic Developers  

A Practical Handbook to the New Developers Telling What They Are and How to Use Them with Reliable Formulae by The Photo Miniature, January...

Modern Photographic Developers  

A Practical Handbook to the New Developers Telling What They Are and How to Use Them with Reliable Formulae by The Photo Miniature, January...

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