1449
forms by Ducos du Hauron in his papers and patents in
1867–9, and was tried by many people. However, Vidal’s
addition of black as a fourth color seems to have been
an important contribution.
Vidal published frequently. His books include: Cal-
culation of Exposure Times (Calcul des temps de pose,
1865, 1884), The Art of Photography Considered from
the Industrial Point of View (L’art Photographique
considere au point de vue industriel, 1868), Practical
Treatise on Carbon Photography (Traite pratique au
photographie du charbon, 1877), Practical Treatise
on Phototypie (Traite pratique de Phototypie, 1879),
Photography Applied to the Industrial Arts of Repro-
duction (La Photographie appliquee aux arts indus-
triels de reproduction, 1880), Practical Treatise on
Photoglyptie (Traite pratique de photoglyptie, 1881),
Practical Manual of Orthochromatism (Manuel pra-
tique d’orthochromatisme, 1891), Color Photography
(Photographie des Couleurs, 1897).
He also sat on and wrote or edited reviews and jury
results at a number of exhibitions and conferences.
Some examples are: Rapport du Jury classe X, Exposi-
tion Internationale des Sciences et des Arts Industriels,
1886, La Photographie a l’exposition de 1889, Rapport
du jury internationale, classe 12, Exposition Universelle
Internationale de 1889, Discourse on photogravure and
photochromographie at the Exposition Internationale de
Photographie de 1892, Rapport du jury internationale,
classe 12, at the Exposition Universelle in Paris, 1900,
as well as a major portion of the Musee Retrospectif
de la photographie a l’Exposition Universelle de 1900
(reproduced in Bunnell, P.C., ed., The Universal Paris
Exposition of 1900: Two Catalogs, Arno Press, 1979).
In his book on Orthochromatism cited above Vidal
reproduces opposite the title page three images of the
same mixed-fl ower bouquet, taken with black and white
fi lm through three different color fi lters. In each one
almost every bloom takes on a different shade from
white to black, illustrating that the varied sensitivities
of black and white fi lm create an illusion of reality in
the fi nal image, which does not correspond to the truth.
Only panchromatic fi lm can capture the entire spectrum
we see. Vidal quotes Hermann Vogel, the discoverer of
photosensitizing dyes as his opening text. Vidal also
provides one of the earliest compilations of sensitom-
etry curves on pages 36 and 37, taken from the work of
Josef Eder and others. There you can see the dyes with
the farthest reach of sensitivity in the red are quinoline
red and cyanine. These represent among the fi rst of
their chemical family, one that is still important in fi lm
sensitization.
Vidal taught at the Conservatoire des Arts et Metiers
in Paris, in Limoges, and occasionally in Marseilles.
He was an active member of the Societe francaise de
photographie. He traveled to the International Photog-
raphy Congress held at the 1893 Columbian Exposition
in Chicago. There he proposed an idea for a museum
of documentary photography. Later that he year he
founded the Association du Musee de Photographies
Documentaires in Paris.
He was an offi cer of Public Instruction and made
a Chevalier of the Legion of Honor (Chevalier de la
Legion d’Honneur).
In the Moniteur de la Photographie he wrote (no.
23, Feb. 15, 1866, 178–180 and no. 24, March 1,
1866, 186–88) “We want photography, so useful to
all branches of knowledge, to become the domain of
everyone...Industry should aim to make photography
for everybody as mechanical as possible in use.” He
certainly did all he could throughout his life to make
this wish to come true.
William R. Alschuler
See also: Poitevin, Alphonse Louis; Woodburytype,
Woodburygravure; Expositions Universelle, Paris
(1854, 1855, 1867 etc.); Vogel, Hermann Wilhelm;
Eder, Joseph Maria; and Société française de
photographie.Further Reading
British Journal of Photography Almanac, 1907.
Johnson, W.S., Nineteenth Century Photography: An Annotated
Bibliography, 1839–1879, Boston: G.K. Hall, 1990.
Focal Encyclopedia of Photography, London and New York,
Focal Press, 1965.
Eder, J., History of Photography. Trans. Epstean, E., New York:
Dover, 1972.
Bellone, R. and Fellot, L., Histoire Mondiale de la photographie
en couleurs, Paris: Hachette Realities, 1981.
Vidal, L., La voie nouvelle en photographie, Le Moniteur de la
Photographie. No. 23, February 15, 1866, 178–80, and no.
24, March 1, 1866, 186–8, quoted in Frizot, M. Editor. New
History of Photography, Koln: Koneman, 1998, 236.
op ten Hofel, K. and Gohr, S., Farbe im Photo, Koln: Haubrich-
Kunsthalle, and Leverkeusen: Agfa Foto-Historama, 1981.
N.A. Photo-gazette. Paris: 25 February 1892.
Konig, E. and Wall, E.J., Natural Color Photography, London:
Iliffe and Son, 1906.VIENNA INTERNATIONAL EXHIBITION
AND VIENNA TRIFOLIUM (1892)
The Vienna International Photography Exhibition,
Ausstellung Kunstlerischer Photographien, was held in
Vienna from April 30 to May 31, 1891 [The American
Amateur Photographer, Jan. 1891, 34] under the patron-
age of Archduchess Maria Theresia, and sponsored by
the Club der Amateur-Photographien under the direction
of Carl Srna, Dr. F. Mallmann, and Carl Ulrich.
Much of the event’s importance revolved around
the organizers’ decision to limit the exhibition solely
to artistic photography to the exclusion of technical