This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
(See Camera, Panoramic.)
The paper base upon which various emulsions are placed for printing processes must be specially prepared in order that they may be as chemically pure as possible. WHATMAN'S drawing paper, also the STEINBACH and the RIVES papers are the ones generally used by photographers who sensitize their own paper. The smooth side of the paper should always be used. There are various surfaces, however, as well as thicknesses of papers, the coarser or rougher surface papers being used where special artistic effect is desired.
A thick, porous, unsized paper. Quickly absorbs any superfluous solutions from anything laid against it. Chemically pure paper only should be employed for drying prints. Cheap blotters contain " hypo " and other impurities, which are ruinous to photographs.
An unsized paper having a thick and woolly texture. Used for filtering solutions.
White blotting paper, stained blue by immersion in litmus solution and dried. Used as a test for acids. Acids change the blue color to red. Litmus is a vegetable coloring material. If the litmus paper turns red on exposure to air, it may be restored to the blue color by holding over the fumes of ammonia.
A paper having a matt or dead surface. When sensitized it gives very artistic prints.
Transparent paper coated with an emulsion in practically the same manner as glass is coated for dry plates.
Oiled paper may be prepared by brushing sheets of paper with boiled oil, and then suspending them until dry.
An imitation of parchment prepared from ordinary unsized paper by immersing it for a few seconds in a solution of two parts sulphuric acid and one part water, at a temperature of 6o° Fahr., then washing it in cold water and removing any remaining traces of the acids by dipping it in a weak solution of ammonia. Paper so treated resembles parchment in appearance, is rough, translucent, glossy, and practically unaffected by water.
A chemically pure grade of paper used as a base upon which to place sensitive emulsions; usually employed by those who desire to sensitize their own papers. Manufactured at Rives, France.
A paper coated with a solution of some soluble chloride. Afterwards it is floated on a silver nitrate bath. As the image is not at all thick the texture of the paper will show in the final print. Albumenized paper containing a chloride is sometimes termed a salted paper.