Eder, Josef Maria

(b. Krems, Austria, 16 March 1855; d. Kitzbühel, Austria, 18 October 1944)

chemistry, photography.

Eder went to Vienna to study chemistry and remained there for his entire professional life. His first independent research was carried out in a competition to explain the reaction between chromic acid or chromates and organic substances, especially gelatin, which in chromate becomes insoluble when exposed to light. He found in 1878 that a labile chromium dioxide is formed and easily decomposes into the lower and higher oxides. This study earned Eder first prize, and he decided to devote his life to photochemistry and photography. He became assistant professor at the Technische Hochschule in 1880 and professor of chemistry at the state vocational high school in 1882. There he founded an institute for education and research in the graphic arts, directing it from its beginning in 1889 until he retired in 1923.

In 1881 Eder extended and improved the use of silver chloride in gelatin emulsion by the method of precipitation, washing, and developing by ferrous citrate or hydroquinone. Such emulsions and techniques became important in the production of transparencies and copying papers. Eder became interested in sensitometry in 1884. He measured the effect of adding the dye eosin to silver chloride or bromide in gelatin or collodion emulsion by determining the depth of “blackening” after exposure for various lengths of time in specific regions of the solar spectrum. He found advantages in using the iodine derivative erythrosin with eosin. With monobromofluorescein and the methyl violet that others had recommended, Eder obtained sensitivities of silver bromide-collodion emulsions that made them suitable for the autotype process of printing in three colors. He recommended mercury oxalate for measurements in the ultraviolet. From spectrophotometry he went to the use of a concave Rowland grating with 13,000 lines per inch for the spectra of many elements, including those of the rare earths.

In 1884 Eder published the first volume of an extensive handbook of photography that grew to four volumes and appeared in a second edition in 1892. Eder was responsible for subsequent editions and enlargements. He also started a yearbook of photography and reproduction techniques in 1887; its thirtieth volume appeared in 1928. His history of photography saw several German editions and was translated into English by Edward Epstein in 1945.

BIBLIOGRAPHY

I. Original Works. Eder’s books were published in Halle. In later editions, the four volumes of the Handbuch were divided into parts, as follows: 1, pt. 1, Geschichte der Photographie (4th ed., 1931); pt. 2, Photochemie (1906); pt. 3, Photographie bei künstlichem Licht, Spektrumphotographie, Aktinometrie (1912); pt. 4, Photographische Objektive (1911); II, pt. 1, Die Grundlagen der Negativ-Verfahren (1927), written with Lüppo-Cramer; pt. 2, Photographic mit Kollodium Verfahren(1927); pt. 3, Daguerrotypie, Talbotypie, und Niepcotypie (1927), written with E. Kuchinka; pt. 4, Autotypie (1928), written with A. Hay; III, pt. 1, Fabrikation photographischer Platten, Filme, und Papiere (1930), written with F. Wentzel; pt. 2, Verarbeitung der photographischen Platten, Filme, und Papiere (6th ed., 1930), written with Lüppo-Cramer. M. Andresen, and Tanzen; pt. 3, Sensibilisierung und Desensibilisierung (1930), written with Lüppo-Cramer, R. Schuloff, G. Sachs, J. Eggert, W. Ditterle, and M. Biltz; pt. 4, Sensitometrie und Spektroskopie (1930); IV, pt. 1, Die photographischen Kopierverfahren mit Silbersalzen und photographische Rohpapiere (1928), written with F. Wentzel; pt. 2, Pigmentverfahren usw. (4th ed., 1926); pt. 3, Heliogravüre und Rotationstiefdruck (1922); pt. 4, Lichtpausverfahren und Kopierverfahren ohne Silbersalze (1929), written with A. Trumm. His other works include Atlas typischer Spektren(1911); and Rezepte, Tabellen, und Arbeitsvorschriften für Photographen und Reproduktionstechniker (13th ed., 1927).

II. Secondary Literature. Obituaries and biographies include W. Greenwood, in Photographic Journal, 86A (1946), 266 ff.; O. Kempel, in Österreichische Naturforscher und Techniker (Vienna, 1951), pp. 125–127; and Erich Stenger, in Zeitschrift für wissenschaftliche Photographie, 8 (1948), 255–256.

Eduard Farber