Sarah Greenough

Alfred Stieglitz was a superb photographer who mastered many different methods of making negatives and prints. He was trained in Berlin in the 1880s by noted photochemist Hermann Wilhelm Vogel. Stieglitz applied the rigorous scientific discipline he learned under Vogel to his photographic practice throughout his life. As he tested his skills in the 1880s and 1890s, he wrote many articles in German, British, and American photographic journals detailing his experiments with different photographic processes. Although he published few technical articles after 1900, he nevertheless continued to explore a wide variety of photographic materials and technical developments. His writings, along with scientific analysis of his prints, provide insight into his extensive experimentation and the ways in which he sought to perfect his art.

Throughout his career, Stieglitz used large-format cameras that took 3 1/4 × 4 1/4-, 4 × 5-, and 8 × 10-inch black-and-white negatives. Although his early negatives were made on glass plates, around the turn of the twentieth century he switched to film, which had become widely available. Both kinds of negatives are coated with a gelatin emulsion made light-sensitive with silver salts. After exposure in a camera, the plates or film are developed and fixed, forming a negative image consisting of silver metal particles. In the 1890s and early 1900s, Stieglitz frequently enlarged his negatives; after 1910 he made contact prints the same size as the negative.

Soon after he began making photographs, Stieglitz became entranced with the recently introduced platinum paper. Throughout the 1890s, as he sought to secure his position as one of the leading photographers of his time, he explored a wide variety of printing methods, including carbon, gum bichromate, and photogravure. These processes allowed him to make enlarged prints from his negatives, which he believed at the time to be better suited for exhibitions. Like many other photographers of the period, he also made numerous lantern slides in the 1890s, which he exhibited in annual photographic salons. In 1907, when the color Autochrome process was invented, he utilized it, while in the mid-1910s, as platinum became more expensive, he made both palladium and silver-platinum prints. Beginning in the early 1920s, he started to use gelatin silver photographic paper, which he continued to employ until he stopped making photographs in 1937.

Constance McCabe

The Autochrome, a positive color transparency on glass, was invented by Auguste and Louis Lumière in 1907 and manufactured by them until 1933. Autochromes were made by coating a glass plate with a sticky varnish and dusting it with a layer of randomly distributed, translucent potato-starch grains. These grains, which were dyed red-orange, violet, and green, were then interspersed with fine black carbon dust, and again varnished. The plates were next coated with a light-sensitive gelatin silver-bromide or silver-iodide emulsion. When the plate was inserted into a camera, the light from the lens passed through the dyed starch grains, which acted as color filters before reaching the emulsion. After exposure, the plate was processed to make a unique, full-color, positive silver image.

Alfred Stieglitz learned the Autochrome process while traveling in Europe in 1907 with photographers Frank Eugene, Heinrich Kühn, and Edward Steichen. He made Autochromes from 1907 through 1918, often of friends and family and while he was on vacation at his home in Lake George, New York.

Courtney Helion, Joan M. Walker, and Constance McCabe

Unlike silver and platinum printing methods that rely on the light-sensitive properties of metal salts to form a metallic image, the carbon process depends on the light sensitivity of dichromated gelatin. This material hardens in proportion to the amount of light it receives, forming an image that consists of pigment in gelatin. To make a typical carbon print, a sheet of paper is coated with a solution of gelatin, potassium dichromate, and pigment. Once dry, this light-sensitive “carbon tissue” is placed in contact with a negative and exposed to light, locally hardening the carbon tissue. The exposed tissue is then transferred to a paper support by wetting both papers, placing the tissue face down onto the new paper, and squeegeeing the pigmented film into firm contact. Under water, the exposed carbon tissue is carefully peeled away. The unexposed pigmented gelatin dissolves in the bath, and the positive carbon print is revealed on the new paper support.

Introduced in 1855 by French chemist Alphonse-Louis Poitevin, and perfected in 1864 by British chemist and physicist Joseph Swan, the carbon process was moderately popular throughout the latter part of the nineteenth century. The Autotype Company of London was the predominant firm that made and sold these tissues commercially. They were available in a variety of hues, in addition to the “carbon” black from which the name of the process derives, capable of fine detail and a lustrous surface.

Alfred Stieglitz was a champion of the carbon printing process, claiming, “On artistic grounds, there is but one printing process which holds its own with the platinotype, and that is carbon” (American Amateur Photographer, 1892). He believed it to be “undoubtedly the most beautiful of the photographic processes, although not as simple as the platinotype” (American Amateur Photographer, 1893). He made and widely exhibited carbon prints in a variety of hues during the mid- to late 1890s.

The eleven carbon prints in the Key Set have characteristics that are both similar to and different than other processes used by Stieglitz. Like his early platinum prints, his carbon prints range in hue from warm browns to neutral blacks and grays. But unlike his platinum prints, which are on smooth or slightly textured paper, he chose heavyweight, rough-textured watercolor papers to make his carbon prints. Stieglitz’s print A Wet Day on the Boulevard, Paris shows the surface texture of the watercolor paper.

A Closer Look: Identifying Carbon Prints

The darker regions of most carbon prints appear glossier than the lighter tones. These dark areas are thicker than the lighter regions because they received more light, and thus more gelatin was hardened, during exposure. This image relief, while sometimes subtle, is a characteristic that helps to identify a carbon print.

Stieglitz’s An Icy Night provides visual evidence of the transfer of the carbon tissue to produce the final print: a bubble was trapped between the tissue and the receiving paper, burst when it was squeegeed flat, and was subsequently retouched to diminish the appearance of the flaw.

Technical analysis can also assist in identifying carbon prints. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) analysis performed on Winter, Fifth Avenue detected gelatin at the surface of the print. Elemental analysis by x-ray fluorescence spectrometry (XRF) found that more chromium is present in the darker areas. Taken together, these results provide strong evidence that the image was formed with dichromated gelatin, indicating that the carbon print process was used.

The ATR-FTIR spectrum shows peaks characteristic of gelatin, indicated with an asterisk (*) in the figure.

The signal for chromium (Cr) detected by XRF is more intense in the darker image areas (Dmax) than in lighter image areas (Dmin).

Sarah S. Wagner

Most twentieth-century black-and-white photographs are gelatin silver prints, in which the image consists of silver metal particles suspended in a gelatin layer. Gelatin silver papers are commercially manufactured by applying an emulsion of light-sensitive silver salts in gelatin to a sheet of paper coated with a layer of baryta, a white pigment mixed with gelatin. The sensitized paper is exposed to light through a negative and then developed out—that is, made visible in a chemical reducing solution. William Henry Fox Talbot introduced the basic chemical process in 1839, but the more complex gelatin silver process did not become the most common method of printing black-and-white photographs until the late 1910s. Because the silver image is suspended in a gelatin emulsion that rests on a pigment-coated paper, gelatin silver prints can be sharply defined and highly detailed in comparison to platinum or palladium prints, in which the image is absorbed directly into the fibers of the paper.

From the 1880s through the turn of the twentieth century, Alfred Stieglitz published articles about his experiments with early silver papers in which the image was printed out, or made visible through exposure to light, but no examples exist in the Key Set. From the early 1920s through 1937, he printed on a variety of commercial developing-out gelatin silver papers. The surfaces of his prints range from matte to glossy.

During World War I, when his preferred platinum papers became difficult to obtain, Stieglitz, along with other photographers, experimented with a variety of silver gelatin papers that mimicked platinum prints (also known as platinotypes). These new faux platinum alternative photographic papers, which were introduced as early as the 1890s, often featured “platino” in their names, such as Platino Matte Surface and Platino Bromide. These papers, offered in a variety of velvety surfaces, provided prints that were advertised as difficult to distinguish from ones made using platinum papers. The matte surface of these silver papers could be imparted by avoiding very smooth paper supports and adding matting agents to the binder such as starch and silica. Various metal salts could be adjusted to create the black and sepia hues typical of platinum prints.

Stieglitz grew to appreciate the surface of the Japine Platinotype that he used during the 1910s. He experimented with gelatin silver papers with semigloss surfaces similar to Japine, along with the occasional matte-surfaced gelatin paper, perhaps to see if the appearance of a new product could match his favorite platinum papers. Stieglitz took the additional step of waxing his silver prints to impart a subtle sheen and a surface appearance similar to Japine.

Suggested Reading

McCabe, Constance. “Coatings on Photographs by Alfred Stieglitz.” In Coatings on Photographs: Materials, Techniques, and Conservation, edited by Constance McCabe, 300–313. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2005.

Wagner, Sarah S. “Manufactured Platinum and Faux Platinum Papers, 1880s–1920s.” In Platinum and Palladium Photographs: Technical History, Connoisseurship, and Preservation, edited by Constance McCabe, 144–183. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2017.

Constance McCabe

Like carbon prints, the gum bichromate print process is based on the light-sensitive properties of dichromated colloids. The gum process was patented in 1855 but did not gain widespread popularity until the 1890s. The paper is coated with a solution of gelatin or gum arabic, potassium dichromate, and pigment. Once dry, the sensitized paper is exposed to light through a negative to harden the light-sensitive dichromated gum in direct proportion to the amount of light it receives. After exposure, the print is washed with water, leaving behind the hardened, pigmented gum, which forms the positive image. The gum process can be manipulated during processing with brushwork, variations in temperature, or by controlling the force of the water. It is also possible to create “multiple” gum prints by resensitizing already processed gum prints with additional coatings of gum solution in different colors. Platinum prints can also be sensitized with a gum solution and printed again, creating “gum-platinum” photographs.

Although few are extant, Alfred Stieglitz made gum bichromate prints at the turn of the twentieth century. There are no examples in the Key Set.

Constance McCabe

Lantern slides are positive transparent photographs made on glass and viewed with the aid of a “magic lantern,” the predecessor of the slide projector. Lantern slide plates were commercially manufactured by sensitizing a sheet of glass with a silver gelatin emulsion. The plate was then exposed to a negative and processed, resulting in a positive transparent image with exceptional detail and a rich tonal range. Lantern slides were used for home entertainment and public lectures, and they were displayed in photographic exhibitions.

Alfred Stieglitz made lantern slides throughout the 1890s. He published numerous articles on how to create more effective lantern slides and he frequently exhibited them at camera clubs and in photographic exhibitions. There are no examples in the Key Set.

Sarah Greenough

When Georgia O’Keeffe assembled the Key Set of Alfred Stieglitz’s work after his death in 1946, she considered for inclusion only the mounted photographs in his possession—because she knew that Stieglitz did not consider a work finished until it had been mounted. She also stipulated that his mounts should remain unchanged. Although Stieglitz used vertical mounts for both horizontal and vertical photographs throughout his career, his choice of materials—the size, color, and texture of the mount board and window mat—and his treatment of the photograph itself varied considerably throughout his life.

During the 1880s, Stieglitz most often trimmed a print to the edge of the image and placed it on a cream board that was significantly larger than the print itself (often three times its height and width). After attaching the print to the board, he covered it with a cream, single-ply window mat, leaving a space of about 1/4 inch around the print. For vertical prints, he often left twice as much space at the bottom of the board than at the top; for horizontal prints, he usually left two-and-one-half times as much space at the bottom of the board than at the top.

In the 1890s and early 1900s, when Stieglitz prepared his large carbon prints for display, he frequently mounted the print on a cream board and matted it with an eight-ply board covered with cream Japanese vellum. Sometimes the window mat covered the edge of the print, and sometimes he left a space of 1/4 inch around it. For vertical prints, he often left twice as much space on the bottom than on the top; for horizontal prints, he often left three-and-one-half times as much space at the bottom than at the top.

Around 1910, when he was preparing the large (approximately 13 1/4 × 10 1/4-inch) photogravures that he made at this time, Stieglitz dry-mounted the print onto a cream board and covered it with a cream window mat (often 25 × 18 1/2 inches), leaving a space of 1/4–1/2 inch around the print. For vertical prints, he frequently left twice as much space at the bottom than at the top.

In the mid-1910s, Stieglitz frequently selected a light beige mount board that was more elongated and not as wide as his earlier boards, often 15 × 20 inches. He used a light beige, single-ply window mat with a toothy texture and allowed it to slightly overlap the edge of the print. For vertical prints, he often left two-and-one-half times as much space at the bottom than at the top; for horizontal prints, he often left three times as much space at the bottom than at the top.

When Stieglitz mounted his early portraits of Georgia O’Keeffe in the late 1910s and early 1920s, he frequently adhered the untrimmed print onto a beige board and covered it with a cream or antique white window mat (depending on the tones of the print) with a smooth surface. For his 8 × 10-inch prints, he often used mounts that were 22 × 18 inches. For vertical prints, he usually left almost twice as much space on the bottom of the print as on the top; for horizontal prints, he usually left two-and-one-half times as much space at the bottom than at the top.

Stieglitz’s method of mounting his prints changed considerably in the 1920s, as he frequently abandoned window mats altogether. He usually dry-mounted a photograph first to the back of a rejected print (to prevent it from curling), then to a thin, white paper board, trimmed the mounted print to the edge of the image, and adhered it onto a cream or sometimes antique white mount (depending on the tones of the print). He mounted his 8 × 10-inch prints onto boards that were approximately 22 × 18 inches. For vertical prints, he usually left 1 inch more at the bottom than at the top; for horizontal prints, he usually left only 1/2 inch more at the bottom than at the top.

With his photographs of clouds made from 1923 to 1934, Stieglitz usually dry-mounted the print to the back of a rejected print (to keep it from curling), which he then dry-mounted to a thin, white paper board. He trimmed the mounted print to the edge of the image and adhered it onto a light cream board. For those photographs made with his 4 × 5-inch camera, he usually used a board that was 13–14 inches high and around 10 3/4 inches wide. For vertical prints, he usually placed them slightly above the center; for horizontal prints, he usually left about 1 inch more at the bottom than at the top.

In the 1930s, Stieglitz continued to eschew window mats. Instead, he dry-mounted a photograph to the back of a rejected print (to prevent it from curling), then often dry-mounted it to a thin, white paper board. He trimmed the mounted print to the edge of the image and adhered it onto a cream or sometimes antique white board (depending on the tones of the print). He mounted his 8 × 10-inch prints on boards that were approximately 22 × 18 inches. For vertical prints, he usually left 1–2 inches more at the bottom than at the top; for horizontal prints, he usually left only 1 inch more at the bottom than at the top.

Constance McCabe and Sarah Greenough

Palladium was another metal that photographic paper manufacturers utilized during World War I as a cheaper alternative for platinum. The palladium process is very similar to the platinum process, except that salts of palladium are substituted for salts of platinum to form the final image. In general, palladium prints are warmer and more sepia in hue, although a “black” palladium paper was available. Introduced in 1916, palladium paper was commercially manufactured until the mid-1930s.

Alfred Stieglitz used palladium paper from 1917 through the mid-1920s. Beginning in the early 1920s, he often solarized his palladium prints by manipulating the moisture content of the sensitized paper to achieve a reversal of tones.

Suggested Reading

Greenough, Sarah. “A Great Day for Palladio: Alfred Stieglitz’s Palladium Photographs.” In Platinum and Palladium Photographs: Technical History, Connoisseurship, and Preservation, edited by Constance McCabe, 348–355. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2017.

Constance McCabe

The photogravure is an intaglio print process that was sometimes used to produce high-quality reproductions of photographs in ink. A positive transparency of a photographic image is used to control the etching of a specially prepared metal plate. After etching in an acid bath, the plate is inked and the surface wiped, leaving ink behind in the etched pits. A sheet of damp paper is then placed on the inked plate and printed. Photogravures have a smooth, continuous tonal range, although an extremely fine grain is evident under magnification. Invented by William Henry Fox Talbot in the 1840s, the process was perfected by Karl V. Klíč in 1879 and was popular from the mid-1880s through the 1910s.

Alfred Stieglitz printed large editions of photogravures of his photographs from the mid-1890s to the mid-1910s, most of which he included in his periodicals Camera Notes, Camera Work, and 291, as well as his 1897 portfolio Picturesque Bits of New York and Other Studies. In the early 1910s, he also made larger photogravures of his photographs for exhibition and inclusion in an unrealized portfolio of pictures of New York City.

Stieglitz’s use of photogravure is further discussed in Julia Thompson’s essay “Stieglitz’s Portfolios and Other Published Photographs.”

Joan M. Walker and Constance McCabe

Alfred Stieglitz’s process of choice from the late 1880s to the early 1920s was the platinum print, or “platinotype.” An early adopter of the platinotype, he celebrated the process both for its aesthetic qualities and reputation for permanence.

The platinum print process is based on the characteristics of light-sensitive iron salts, which react with platinum salts to form platinum metal. A sheet of paper is coated with a solution of these salts to make it sensitive to light. Once dry, the sensitized paper is exposed to light through a negative, developed in a chemical solution, cleared, and washed. The print’s hue may range from charcoal gray to sepia depending on the chemical properties of the sensitizer and developer. Various image hues can also be achieved by adjusting the moisture content of the sensitized paper and/or the temperature at which a print is developed. Further chemical additions to the sensitizer and/or developer provide seemingly endless options for fine-tuning the appearance of the photograph.

The first commercially manufactured platinum paper was introduced in 1879 by British inventor William Willis Jr., who perfected the process over the following decades, gradually expanding the variety of his Platinotype Company products. A chemical variant of the platinum process was introduced in 1887 by Austrian Giuseppe Pizzighelli and marketed by several manufacturers in Europe and the United States.

Unlike a gelatin silver print, the image in a platinum print is absorbed directly into the paper, taking on its characteristics. Thus, the paper upon which a platinum print is made affects the quality of the image. An untreated paper will yield a matte print with a softer and less-detailed image than one made, for example, on a paper that has been chemically modified to impart a sheen, such as the Platinotype Company’s Japine papers, first introduced in 1906.

Stieglitz used both matte and Japine papers until manufacturers decreased production of platinum papers during World War I due to restrictions on the use of platinum for nonmilitary purposes. In 1918, he voiced the frustrations experienced by devotees of the platinum print: “A kingdom for some decent platinum paper. Just a few sheets. I see I have run out of paper” (Alfred Stieglitz to Paul Strand, August 22, 1918, Alfred Stieglitz/Georgia O’Keeffe Archive, Beinecke Rare Book and Manuscript Library, Yale University).

A Closer Look: Two Platinum Print Processes

Like others of the time, Stieglitz preferred platinum papers’ matte surface and range of image tones, and he experimented extensively with both Willis and Pizzighelli commercial platinum papers. From 1887 to 1902, he wrote eighteen articles on the platinum processes in which he not only shared numerous recipes for hand-sensitizing papers, but also reviewed commercial products and explained how chemical manipulations could alter the tone of the image from neutral gray-black to sepia.

Willis’s process requires chemical development to complete the formation of a black image; raising the temperature of the developer could produce a warm black image, but a mercury additive was required to achieve a true sepia tone. Pizzighelli’s process, also known as the “direct platinum” or “water-developed” process, requires no chemical development. Only the presence of water, as steam or moisture in the sensitized paper, is required to form the image. In his 1891 essay “Tints of Prints Made on Direct Printing Platinotype Paper,” Stieglitz noted that the tone of the final print could be controlled by adjusting the moisture content of the sensitized paper prior to exposure. If the paper was moistened prior to exposure, a black image would result; if the paper was dried prior to exposure, a sepia image would result.

Three of Stieglitz’s early platinum prints that were made from the same negative (Sunlight Effect, Gutach) illustrate how he exploited the chemical properties of the process to achieve different image appearances. These examples make particularly useful comparisons and provide insight into the young Stieglitz’s artistic choices and practices.

It is possible to detect the metal components of a photograph using a non-sampling, non-destructive analytical method known as x-ray fluorescence spectrometry (XRF). In the case of the three examples of Sunlight Effect, Gutach, platinum is detected in all of the prints. However, the very warm-toned sepia print (Key Set number 185) also contains mercury. Mercury salts were commonly used as additives to both the sensitizer and developer to achieve sepia platinum prints. The lack of mercury in the other warm-toned version indicates that it was printed using Pizzighelli’s direct platinum process and the warm hue was achieved by drying the sensitized paper prior to exposure.

This detail of the XRF spectra for the three prints of Sunlight Effect, Gutach shows that all three contain platinum (Pt) as the primary image metal. Only the sepia-hued print (1949.3.175, Key Set number 185) also has mercury (Hg) in the print, which gives it its warm hue.

Suggested Reading

McCabe, Constance, ed. Platinum and Palladium Photographs: Technical History, Connoisseurship, and Preservation. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2017.

Constance McCabe

During World War I, as the cost of platinum soared, commercial manufacturers looked for cheaper alternatives. “Satista” was the brand name of a commercially made silver-platinum paper introduced by the Platinotype Company in 1914 as a less-expensive substitute for platinum paper. Satista prints are a variant of both the platinum and salted paper printing processes. A sheet of paper is sensitized with successive applications of potassium chloride, silver nitrate, and dilute iron-platinum sensitizer. After exposing the sensitized paper through a negative and developing the image, the print was fixed with two clearing baths—one for platinum, the other for silver—followed by washing. Satista prints may be difficult to distinguish from platinum prints. Alfred Stieglitz made a few examples during World War I.

Suggested Reading

McCabe, Constance, Christopher McGlinchey, Matthew L. Clarke, and Christopher A. Maines. “Satista Prints and Fading.” In Platinum and Palladium Photographs: Technical History, Connoisseurship, and Preservation, edited by Constance McCabe, 124–127. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2017.

Constance McCabe

Inscriptions on 157 palladium prints in the Key Set indicate that the prints were treated by the acclaimed photographer Edward Steichen. The wording of the inscriptions varies; some say “treated by Steichen for stain,” while others say “treated by Steichen” or just “treated” (followed by the date). Soon after Alfred Stieglitz’s death in 1946, Georgia O’Keeffe determined that the tone of many of his palladium prints made from the late 1910s to the early 1920s had changed, becoming warmer or more orange in the highlights of the prints. She asked Steichen, who was once a close friend and collaborator of Stieglitz, if he could improve their appearance and longevity. Steichen successfully treated the prints to improve their appearance but did not document what he had used to reverse the “stains”—and over time, the warmer or more orange tones have reappeared.

Conservators and scientists at the National Gallery of Art recently revisited earlier research into Steichen’s treatment, reinvestigated the palladium process, delved into Stieglitz’s writings, and discovered new information that may help to explain why the discoloration formed initially, what Steichen may have done to treat the prints, and why the warmer tones seem to have returned. The results of this new research showed that the lighter regions of an improperly cleared palladium print will develop staining or discoloration due to residual iron left in the paper. This suggests that Stieglitz’s failure to sufficiently clear his palladium prints may be at the root of the problem. The discoloration on poorly cleared laboratory-created test prints visually decreased when treated with a sodium acetate solution, which Steichen might have used to reverse the original discoloration. But the discoloration on the test prints treated with the sodium acetate solution reappeared after artificial aging—just as the discoloration on the prints treated by Steichen have.

Suggested Reading

McCabe, Constance, Christopher A. Maines, Mike Ware, and Matthew L. Clarke. “Alfred Stieglitz’s Palladium Prints: Treated by Steichen.” In Platinum and Palladium Photographs: Technical History, Connoisseurship, and Preservation, edited by Constance McCabe, 356–371. Washington, DC: American Institute for Conservation of Historic and Artistic Works, 2017.