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.
576. Before entering upon the detailed instruction we will first give a description of the different grades of paper to be used. Bromide paper is a pure photograhic paper coated with a sensitive emulsion composed principally of pure bromide of silver and white gelatin, only enough gelatin being used to cause the sensitive silver salt to adhere to the paper. The Bromide of Silver emulsion is so compounded that it will give a pure black tone when exposed to light for a brief period of time and then developed, the unexposed portions of the paper remaining perfectly white except in the papers of the class of Royal Bromide, which has a delicate cream tint.
Grades Of Paper. Bromide papers are manufactured in different grades and qualities, ranging from a heavy rough to a thin smooth in the matte surfaces and in the glossy papers from the enameled to the matte-enamel. Each of these various kinds of Bromide papers are generally made in two varieties of emulsion marked either "hard" or "soft." "Hard"-strong contrasts for use with soft or flat negatives. "Soft"-soft and rapid for use with hard or strong, contrasty negatives. The papers manufactured by the Eastman Kodak Company are probably the best known and can be used as a standard.
578. Platino-Bromide paper gives Platinum-like results. It has a fine surface and is best adapted for enlargements from original negatives-not copies. This paper is made in two weights-A, thin smooth; C, heavy rough. The C, heavy rough, is intended for enlargements of more than ordinary size which are to be spotted or finished in crayon, pastel India-ink, water-colors or oil.
579. Standard Bromide paper is adapted for all kinds of enlargements, particularly copies on which crayon or pastel work is to be done. The emulsion is coated on three different weights of paper-A, thin smooth; B, heavy smooth; C, heavy rough.
580. Matte-Enameled Bromide paper gives rich carbon blacks and has a smooth, velvety, matte surface, tinted just enough to lend warmth to the high-lights and half-tones, giving an effect not heretofore obtained with Bromide papers. When used with a negative made direct from a subject-not from a copy-enlargements can be made that closely resemble matte contact prints.
581. This paper gives excellent sepia tones, and is especially recommended when it is desired to make plain prints without hand work for enlargements 16 x 20 and under. It is furnished in medium-weight only.
Enamel Bromide Paper. A glossy Bromide paper, which, when used with direct negatives-not copies-gives enlargements closely resembling glossy contact prints. It affords excellent sepia tones and can be finished in water-colors washed in by brush or with the air-brush. When squeegeed to a ferrotype plate a gloss is produced which is fully equal to that produced by the glace process. It is furnished in medium-weight only.