7. Wash a photographic effect is desired a wash drawing is usually best, since it re produces not only blacks and whites, but intermediate tones. Wash drawings are in some respects superior to photographs. Details which have selling quality may be given the right degree of emphasis, perspec tive may be rightly represented, and backgrounds may be added or taken away. The texture of a filing case, or piano or a chair having massive lines may call for this form of reproduction. The wash drawing is often preferred as a matter of economy, since the desired effect may be secured more easily in wash than in a retouched photograph.
8. Oil developments in color printing have created a growing demand for "copy in color." The direct color-photograph is sometimes too faithful a likeness of the object. The oil painting when correctly executed, 'makes ideal color copy. The cost of good oil paintings and the time required for successful execution necessarily restrict their use.
The Liggett and Myers Tobacco Company, in its reproductions of paintings in Fatima cigarette adver tising, employs paintings of distinct artistic value.
9. Retouched camera makes no allowance for poor or unequal lighting. Some color values it fails to bring out; others it indicates wrongly. A commercial photograph as received from the pho tographer nearly always needs to be retouched. Such retouching brings out contrasts and adds details.
10. Sources of art advertiser may procure his illustrations from several sources. These include the art department of an advertising agency; an art organization ; a "free lance" artist who is trained in the business requirements of art work; the art departments of photo-engravers; the art depart ments of periodicals and newspapers ; and the stock cut organizations that supply ready-made cuts.
11. Kinds of are three general methods of engraving. The first employs raised characters, in the second the characters are sunken, while the third makes use of surface characters. All engraving is done by one of these three general pro cesses or a modification.
Printing from raised characters is the oldest method. The parts that are not to appear are cut away or kept below the printing surface. Surface printing is used mainly in one process—lithography. A plain surface may be made to "take ink" in one place and "refuse ink" in another, by special treat ment. When paper is impressed upon the surface,
that part which is inked prints, the remainder leaves the sheet blank.
The advertiser is necessarily concerned with the relative advantages of the various methods of en graving. On a catalog run he may use zinc etchings, photo-engravings, wood cuts or lithographs thruout. For the covers of the book he may use any of these mediums or he may use one of the embossing proc esses, either wholly or in part. Each process has its merits and its limitations.
12. Wood cuts were made when printing was first invented. Playing cards and re ligious pictures were cut on wood as early as 1400, and advertisers used wood cuts up to about 1880. Altho later engraving processes have largely sup-; planted this method, wood engraving is still em ployed for illustrations of machinery and similar subjects. The cost of the engraving is relatively high, but the printing costs no more than letter press work.
The accompanying reproduction of a wood engrav ing, used in the Millers Falls Company's advertise ment, shows the present-day use of the wood cut process. The varying textures and surfaces are brought out by differing methods of lining and dot ting.
13. Zinc the process of zinc etching, the copy is photographed and the negative is made on glass. The developed- film is toughened, removed from the glass and remounted in reversed position on another glass. A zinc plate, having one surface highly sensitized, is clamped to the glass negative. Light, either from the sun or from an electric arc, is applied to print the photographed copy on the zinc. Ink applied to the plate adheres only to the exposed parts, the remainder coming off after a bath in run ning water. After drying, a red powder termed "dragon's blood" is dusted over the plate; this ad heres to the inked portion and is brazed on it.
The actual etching is now done. Immersion in a solution of nitric acid and water cuts the zinc, except where it is protected by the "dragon's blood." After the plate has been subjected to the mechanical proc esses of "routing," and mounting to type height, it is ready for use.
Zinc etchings may be prepared from any copy made up of solid lines, points or contrasting surfaces.