Colored Photography Discovered at Last.

Oamaru Mail, Volume XXIII, Issue 7370, 18 November 1898, Page 1

Colored Photography Discovered at Last.

EVERY HUE OF FLOWER, TREE, GRASS, OR ANY OTHER OBJECT ACCURATELY REPRODUCED.

Chicago, 111., Feptembe.' 24.—Co'or photography has been made a final success by a Chicago man. The process of using ;ui ordinary camera and in one-fifth of a second accurately photographing all of the brilliant hues of a flower garden, all the contrasts in green of a landscape, all the wonders of a summer sky, the jewel upon your finger, the ribbon at your throat, the stripes in your clothes, the decorations of your hats, the bouquet on your lapel, is now a reality. Kot a canvas of the old masters but may be reproduced, with every tint of the original. This discovery and its practical applica<ion is the work of Iste James W. M'Donough of Chicago. He has been dead a year, but what he discovered has been in the hands of friends and business associates ever eince. What he discovered is duo primarily to the dirty lmk. nasty condition of the Chicago Biver. Crossing the river oti the Madison-street Bridge one day, in 1870. Mr M'DoDough noticed on the surface of the murky water the colors of the spectrum caused by escaping oil from some near-by warehouse. The thought came to him that the river would present a beautiful spectacle if covored with those colors. His second thought was as to why that river's surface could noli be photographed. From this thought gradually developed and grew the process of color photography—the first ever given to the world—that will always be know a as M'Docough's. Mr M'Donough was in the early years of his life wealthy and given to scientific pursuits. His work in connection with the telephone was primarily alocg the lino to the discovery of the receiver, and he fought his rights in the courts until he and all others were defeated. Worn in health and weakened in fortune Mr M'l'onough turned from the telephone to his old dreams of color photography, and pursued them until satisfied that the worlt could be done. He died just as siccess was at hand. The process that he created is a color photography which is purely mochanical. The ordinary camera is used, and the negatives are produced and developed by the usual processes, before exposing the negative in the camera a transparent scresn ruled with the three primary color* is interposed between the negative and object to be photographed. . . After developing the negative positive plate is produced from it, which, viewed by itself, does not differ from ihe ordinary black and white plate, but when it is laid upon a viewing screen, ruled with the primary colors, a duplicate of the taking screen used in the camera, the colors in the object photographed appear. lhe principle of color photography is a mixture of colored lights on the retina. A transparent mediam is ruled in fine colored lines, 300 to 600 to the inch. These lines are red, blue and green, commonly speaking. They are the fundamentals of the spectrum the yellow of school days now being rejected—and their mixture produces whito light. In other words, the color of each is such as to absorb the remaining two and transmit only its own light. To make a picture it is necessary to place one of these ruled soreens in immediate contact with the sensitive surface of the dry plate and expose the same as in ordinary photography. The sensitive plates must be what is known as isochromatic plates—that is", sensitive to all the colors of the speotrum. , ~. . , After a negative is made a positive is also made by contact printing, as in the usual manner. This positive is then placed over the ruled screen and the dark lines on the positive are made to register with the coloured lines on the screen. When this is done the picture is seen in its natural colours. , , ... Paper photographs are made by printing in the usual manner on the sensitive paper ruled with the three colored lines, as on tho screen. Half-tone pictures in colors are also made by printing with black ink—from a half-tone plate made from tho original—upon paper having the three colored linen ruled on its surface, the same as a Bcrcon. M'Donough the day before his death photographed himself in one of the flower gardens of Jackson Fark. He never lived to see the picture completed, but it stands to-day in an office in Dearborn-street with every hue of the blossoms surrounding him faithfully reproduced—the work of'the sun and the sun only.