The successful printer of color plates must be a rare artist or else work under the direction of an artist. Little of this work is now done except in Paris and Vienna, and the limited number of color plates of this kind used for book illustration in this country does not warrant the time and expense necessary to train printers capable of doing the work. Even English plates are usually sent to Paris to be printed.
It is difficult to describe the work of what is termed artistic printing. Every plate is a subject to be treated by itself, and no hard and fast rule can be applied. It is really a matter of artistic feeling, and to revert to the simile of the angler, one cannot explain how a trout should be played, but can only say that it depends on the fish, the water, and the circumstances. A fisherman can show you, if you are on the spot, and so can the printer.[Back to Contents]
THE GELATINE PROCESS
By Emil Jacobi
Of the many photo-mechanical processes which have come into existence in recent years, the photo-gelatine, next to the half-tone process, has shown the greatest adaptability for practical use in art and commerce.
Whatever the name may be,—Collotype, Artotype, Albertype, Phototype, or Carbon-gravure,—the principle is the same; an impression is made in printer's ink from a photo-chemically produced design on a gelatine surface, either on the hand-press or on a power cylinder press similar to that used in lithographic printing.
There is hardly any process which is more capable of producing fine works of art. It is the only true method for reproducing, in the full sense of the word, an etching, engraving, a drawing in pen and ink, an aquarelle, a painting, or objects from nature. The depth and richness of tone of an engraving, the delicate tints of an aquarelle or india-ink sketch, and the sharpness of the lines of an etching or pen sketch can be reproduced with such fidelity that it is often impossible to distinguish the copy from the original, and this is achieved the more easily as the printing can be done in any color and on any material, be it paper, parchment, leather, or textile goods.
Another great advantage of a gelatine print is its inalterability and durability, no chemicals being employed in transferring the picture to the paper. The picture itself being formed by solid pigments, such as are used in printer's ink or painter's colors, there is no possibility of its fading or changing color, which cannot be said even of platino prints, at present considered the most lasting of all photo-chemical processes.
Like all new inventions, the photo-gelatine process, in its early stages, had to undergo severe trials, and for some years almost disappeared from public view, after many failures precipitated through unscrupulous promoters and inefficient persons who claimed impossibilities for the new process. It took years of patience and perseverance to regain the lost ground and overcome the opposition of those who had suffered by the failure of this process to produce the promised results; but at present it is, in Europe, one of the methods in most general use for illustrating, and in this country it is making steady progress and rapidly finding favor.
The process, simple as it may seem to the casual observer, requires, more than any other photo-mechanical process, skilled hands in its different manipulations to keep it up to the standard of perfection. The following short description will give the uninitiated sufficient enlightenment to think and speak intelligently about it.
The foundation or starting point, as of all the other photo-mechanical processes, is a photographic negative; that is, a picture on glass or some other transparent substance, in which the light parts of the picture appear dark, and the dark parts light in transparency, graduated according to the different shades of tone in the original. The next and most prominent feature is the printing plate. A perfectly even glass, copper, or zinc plate is covered on the surface with a solution of fine gelatine and bichromate of potassium, and dried. This printing plate is then placed under a negative and exposed to the light. The action of the light on the bichromated gelatine forms the basis of this process. In proportion to the graduated density of the negative, the light acts more or less on the bichromated gelatine, rendering the latter, in proportion, insoluble and hardening it. After sufficient exposure the plate is washed out in water to eliminate the bichromate not acted upon by the light, and is then actually ready for the press.