Chapter 10
The Colors of Black and White Photographs
This chapter also discusses tinting and age
deterioration.
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Heterogeneous collections of old photographs appear to be
colored predominantly brown, either from intentional processing
or from the ravages of age.
Photographs that are not colored by a three‑color
photographic process (as opposed to hand tinting) are
customarily called black and white, even though they may be
tinted or gold-toned or other colors. But anyone who has spent
much time searching through assorted old photographs in antique
markets is likely to wonder if there ever were any actual black
and whites. The common survivors seem to be mostly brown or
yellow in varying shades. Some of the reasons for these colors
are:
Original images were sepia or gold toned.
Original images were tinted.
Original paper was tinted.
Binder was dyed
Original images were pigmented (e.g. gum bichromate).
Particle size differences in the image from processing
variations
Residues of processing chemicals
Faded images.
Stained images.
Yellowed paper.
Aging changes in the binder (e.g. gelatin).
Evidence of deterioration can be a revealing clue to the
process by which photographs were made. A comprehensive
discussion of deterioration mechanisms is given by Reilly
[122].
It was recognized in the middle of the nineteenth century that
fading of photographic images on paper was a serious problem.
There were many reasons: individual processing variations,
chemicals were impure and not standardized, and paper quality
was not uniform until Eastman Kodak perfected paper based on
wood pulp in 1926. For forty‑five years the dominant
printing paper was albumen paper with an emulsion coating made
of egg whites.
Considering the sulfur in eggs and the well‑known
affinity of silver for sulfur, it is perhaps surprising that
any of them have survived. Toning with gold or selenium was
commonly used to stabilize images. The effect also somewhat
resembled skin tones, but there was no uniformity, since the
resulting tint depended on the chemistry of the emulsion as
well as the toner. This is true today: the tones may be sepia,
brown, warm black, or blue black. If color is used as a
recognition aid, these variations can create many problems, yet
there are experienced persons who can identify pictures at a
glance. This should be amended to read "sometimes". The bulk of
surviving 19th century prints are either albumen prints or
early silver bromide gelatin prints, so with a little practice
a good average is possible.
Color Measurements
It would be very useful to be able to characterize the colors
of 19th century photographs in a quantitative system that would
provide reliable descriptors. The necessary technology has been
available for some years, and apparently all that is lacking
for feasibility studies is funding and interest. There are two
requirements:
1. The availability of standard specimen photographs
representative of each process in its original condition, or as
well-preserved as possible.
2. Readily available measurement equipment.
The present advanced state of color photography has made
precise color measurements commonplace, but the required
equipment is not cheap or simple. A rigorous method of color
measurement is the determination of the spectral energy
distribution of white light reflected from a specimen mounted
in an integrating sphere. The inner surface of the sphere is
coated with pure white magnesium oxide, and the illumination is
from a standard lamp. The integrated reflected light is
analyzed with a prism or diffraction grating, and the results
mathematically converted to tristimulus coordinates. The
technique is widely used in manufacturing industries such as
paints, fabrics, fluorescent lamps, and dyes. In principle
there is no technical reason for not applying the method to
historical photographs.
Pilling [117] mentions the use of Munsell color chips to
characterize the colors of cabinet card mounts. The Munsell
Color System is a subjective color matching system that under
controlled conditions can give reproducible numbers to three
components of color. These are "hue", the dominant color;
"chroma", the degree of saturation; and "luminance", the
reflected brightness. A photograph consists of mixed shadows
and highlights, and different values of chroma and luminance
will be obtained from different regions of the picture. One
solution is to integrate, or average, the reflected light as
mentioned above. Another is to standardize on matching either
the densest shadows or the clearest highlights, resulting in
numbers that could be referenced by other workers. It would be
a more objective and reproducible system of descriptors than
the use of arbitrary terms such as "faded yellow", for example.
The Munsell System is discussed in Hunt [78, 71; 122]. The
American Society for Testing and Materials (1916 Race Street,
Philadelphia, Pennsylvania 19103), publishes a "Standard Method
of Specifying Color by the Munsell System", No.D 1535‑68
or later revision. ASTM Standards may be on file in engineering
college libraries. The Munsell System of visual color standards
is manufactured by Macbeth Division of Kollmorgen Instruments
Corporation, 405 Little Britain Road, New Windsor, New York
12553.
Visual Appearance of 19th Century Pictures
In the absence of a quantitative measurement scheme, a
practical way to identify unknown specimens is to compare them
to published pictures. The best single reference for paper
prints is Reilly [122], Eastman Kodak publication G-25, 1986.
Bernard [22], Coe & Haworth‑Booth [32], Eastman [47],
and Holme [77] also contain high quality color reproductions of
some 19th century prints that give a good idea of their present
appearance, provided viewing is done in daylight.
Museums and galleries usually have subdued lighting to prevent
fading, often by reduced-voltage incandescent lamps whose light
is reddish. A case in point was a prominent exhibition at the
George Eastman House, of carbon, albumen, and Woodburytypes,
all of which showed remarkably similar rose‑brown
coloration under protective dim incandescent lighting. It is an
inevitable compromise between protective but distortive
lighting, and total inaccessibility to viewing. On the other
hand, this writer has seen original irreplaceable photographs
from the Civil War period exhibited six inches from a forty
watt fluorescent lamp. They were nearly completely gone.
Ignorance is a terrible thing.
The fading of color photographs has been intensively studied in
recent years, and some of the techniques are relevant to black
and white photographs. A significant study (Presented at the
International Symposium: The Stability and Preservation of
Photographic Images, 1982, The Public Archives of Canada,
Ottawa, Canada, sponsored by the Society of Photographic
Scientists and Engineers.) was described by Sergio Burgie in
1982. The paper was entitled "Fading of Dyes Used for Tinting
Unsensitized Albumen Paper".
His results, which unfortunately have not been published
elsewhere, were presented in color slides. The work was based
on a selection of nearly unfaded albumen prints in the
collections of the International Museum of Photography at
George Eastman House. The availability of these standards was
crucial to the study.
In this case the extent of age changes was surmised by
examining margins that were covered by frames or mounts. This
study did not make use of quantitative color measurements. No
comprehensive references that treat the problem of
identification of 19th century photographs by quantitative
color measurements were found during research for this volume.
The Art of Tinting
Enthusiasm for Daguerreotypes and calotypes did not
submerge the desire for colored pictures. If scientific
ingenuity could accomplish a marvel such as fixing images from
nature, surely the achievement of color pictures would be just
around the corner. It proved to be a long corner, but in the
meantime artist's colors were at hand. As Rothery [128]
remarked in 1905, "Color photography is, as yet, in the clouds
and the brush and palette must still be used." There was a
flood of articles on how to color with oils, chalk, and water
colors; some typical ones were by Delery [43; 27], Rothery
[129], and Nicholson [106]. A detailed account of tinting
lantern slides is found in Burbank [28, 148‑159], who
writes the following inimitable hint:
"...the cleanest and most useful dabber is supplied to most
persons by nature, one that is not likely to wear out or get
mislaid, namely, the finger end. Nothing can exceed the
evenness of tint which a practised hand can produce by lightly
tapping the paint on the glass he is working on, which
gradually renders the color even and smooth.
The finger to be selected is that which has the smoothest skin;
generally, the third finger of the right hand is the best. The
skin has always a kind of furrowed surface, and some artists,
hence, rub the end of the finger lightly on a piece of smooth
sand‑paper, by which some of the roughness is removed.
This cure of the furrows is very temporary; nature, in a day or
two, indignant at this treatment of the cuticle, will retort by
growing a skin thicker and rougher than at first, so it is
better for beginners to use their dabbers as they find
them."
Historical research sometimes rewards us with such whimsies. It
seems a curious oversight that the Reverend Burbank did not use
the term "fingerprint" in his 1891 book. The fingerprint had
been used for identification as early as 1858 by Sir William J.
Herschel.
A common form of tinting or retouching was found in crayon
prints, which are discussed in Chapter 8 and in Appendix
II.