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Photography and the Black Arts


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PHOTO-LITHOGRAPHY


During the 19th century, lithography’s dependence on a substrate of heavy limestone nearly doom this promising medium to oblivion. Photographic transfer was very difficult and stones could not be used on fast rotary presses while metal litho-plates were found to be too fragile for extended commercial use. Line block printing, which became its chief competitor, may have overtaken it had it not been for the invention of gelatin tissue. This innovation caused revolutionary changes in lithographic reproduction and returned it to the status of a competitive medium. It would be used to create a new generation of multi color postcards just as traditional chromolithography began to fade. Most early photolithographic techniques would be abandoned by the 1920’s but color lithography would continue to evolve into photo-offset lithography, which is still in use, and produces most of the world’s postcards today.

Photolithography
Sometime around 1852 the French printer Rose-Joseph Lemercier became the first to create a photolithograph. His process basically began by coating a litho-stone with a thin layer of photosensitive asphaltum, which was then exposed to paper negatives. Three years later Alphonse Louis Poitevin patented a similar method, only his process used a photosensitive emulsion of dichromate in albumen or gelatin that was applied directly to the substrate. All early photographic transfers however were made through contact printing with exposure from the sun, and the size and weight of the stones made this procedure very difficult and not commercially viable. This problem was solved in 1864 when J. W. Swan invented a gelatin tissue that could also be photosensitized and exposed away from the substrate, and then later adhered to a stone’s surface. After exposure to a photo negative and washed out, only the light hardened gelatin will remain on top the stone as if it were a drawing. When the stone is dampened and rolled up with a greasy ink, the moisture will sit within the fine polished surface of the bare stone, and the rolling-up ink will only stick to the remaining photo emulsion. It is then lightly etched to chemically stabilize the image on the substrate. Once cleaned it can be printed as a normal lithograph.

Zincography
Zincography was an early form of photolithography designed for use on metal plates. A zinc litho-plate was first coated with a mild acid solution that caused hygroscopic salts to form across its entire surface. A photosensitive asphaltum varnish was then applied and the plate was exposed to a positive transparency. All areas that were exposed to light would harden, and a bath of acetic acid would wash out the rest of the asphaltum. Salts deposited by the original etch were also washed out at this time, except where they were trapped under the hardened areas. The plate would then be coated once more, only now with a dark lacquer varnish (fuchsine). When washed clean with solvent, the lacquer would only continue to stick to the areas where the sensitized asphaltum had hardened. When dampened and rolled with ink the salted areas would hold water and repel ink while the remaining lacquered coating repelled water and attracted ink. As the use of litho-stones diminished, the term zincography was largely forgotten and work printed from photo generated litho-plates, now largely aluminum, is simply referred to as photolithography.



PHOTO-CHROMOLITHOGRAPHY

While the photocrom process was a unique type of photo based printing technique, it was in many ways little more than the natural evolution of chromolithography in the face of advancing technology. The process would largely ignore optical blending and continue to use many separate printing substrates to create of each tone of the same color. Just when the chromolithographic palette seemed to be narrowing, the photocrom process reversed this trend and expanded the use of color. Only now random photographic grain and speckle would replace artist drawn dots and spatter. This technique provided an outlet for the public’s fascination with photography while retaining the colorful look of chromolithographs that they were comfortable with. Although many of the postcards created were far from the truthfulness of a photograph and in the colors of nature that their catalogs boasted of, this was a winning combination that attracted a large market. While a number of companies would develop and even patent similar techniques, those who used this process were so few that variances can be examined through the products of each firm.

Postcard

Photo-Chromolithograph: This postcard may have only been printed in three RGB colors but nine different sones were required to present three relative values of each hue. These subtle differenced in tonality are more noticeable in the enlargement below.

Postcard Detail

Photochromie (Vidal Process)
An early photo-chromolithographic process was invented in 1875 by Frenchman, Leon Vidal that combined traditional chromolithography with elements of the photographic reproductive methods used to create woodburytypes. Duplicate glass plates were made from the same negative for each color required and then the areas not needed to print were covered with opaque ink. Once transferred to a stone, each transparent color would then be printed over a photograph or a woodburytype. This technique produced very high quality color reproductions, but it was such a difficult and expensive process that it was rarely used. After some modifications that created an image entirely in ink, the firm of Nenke & Ostermaier obtained a patent for the photochromie process in Saxony that was based on Vidal’s earlier work. At first they used it to print postcards for other publishers but they eventually began to publish cards under their own name.

Postcard

Photochromie: The details of the rocks on this postcard by Purger & Co. are so realistic and minute that they could have only been based on a photograph despite the coarsely printed grain. The train however is very rigid in appearance indicating it was either heavily retouched to provide more definition or completely drawn in by hand.


Postcard

Photochromie: Even though areas of color on this postcard by Nenke & Ostermaier are too localized if not also too intense to look natural, the image still manages to hold a very strong photo like appearance. This is usually a clear sign that a card is based on a black & white photograph that required the additional hand of a retoucher to add color.


Photochrom Process (Aäc Process)
A continuous tone color lithographic process was first developed in Switzerland in 1886 by Hans Jakob Schmid of Orell Fussli & Company and patented as the Aäc Process in Austria in 1888. The Swiss firm Photochrom Zurich, later renamed PhotoGlob, was specifically set up for the printing of postcards and prints with this process that were referred to as photochoms. They later licensed out this technique to Photochrom Ltd. of England, and the Detroit Publishing Company in the United States. Both licensees made small changes to the way their stones were processed, providing each company’s cards with a distinctive look. For the most part the use of this process ended in the 1920’s as publishers sought out less expensive alternatives, but it remained in use in Switzerland until 1970. Today a nearly identical look can be achieved with screenless offset lithography that only uses four process colors.

NOTE: Photo-chromolithographic photochroms should not be confused with photochromes used to reproduce natural color through tricolor printing.

Postcard

Photochrom: Unlike the color fields in traditional chromolithography where many multiple color dots were employed to create a subtle appearance, the color fields in postcards by Photogob were made up of small markings of very similar hues. While this provided their cards with greater color intensity, it also flattened out the space in many of their compositions. The dichotomy between detailed rendering and flat color within the same image created a distinct mannered look that was typical of photochroms. This unusual contrast is evident in the two details below.

Postcard Detail

Postcard Detail

The Photochrom process begins with multiple litho-stones that are coated with a photosensitive Syrian asphaltum (bitumen) dissolved in benzene. When dry, all the stones are then all exposed to the same photo negative through contact printing. No line screens were used in any part of this process. The bitumen hardens in proportion to its exposure to light, and the unhardened areas are then washed away with solvent. At this point the retoucher removes all parts of the image not relevant to the color assigned to that stone (photo-stone) while adding in any texture that is needed. Wool daubers and fine hairbrushes were often used with touche to finely adjust the tonal balance, which required a very delicate hand. In some cases new compositional elements would be removed or drawn in. Each stone then went through a very complicated etching process, which is where most of the technique’s trade secrets lay. This manipulation of processing variables determined the nature of how and where the ink grain printed, which controlled the postcards final look. The stones were then printed in the same manner as a normal chromolithograph. At least six separate stones were required for this process, though the employment of ten to fifteen hues was more typical. The resulting images could capture a fair amount of detail with a great clarity of color even though completely broken down into small granules; but since they were based on black & white photographs, the handling of color by retouchers could render the same image either realistic or highly mannered.

Postcard

Photo-Chromolithographs: While photo-chromolithographs usually have a strong photo-like continence despite their rough grain, extensive retouching can often defeat this look. Colors have been so altered on this postcard above that they not only appear unreal, they distort the pictorial space. The limited palette on the card below has produced a dull image more typical of a tinted halftone than one produced through photo-chromolithography.

Postcard

In 1888 the Wezel & Nauman Fine Arts Company patented their own photocrom process in Germany a day after Orell Fussli filed their patent in Austria. From about 1890 most of their postcards were printed on artificial lithographic stones, a product of their own invention. Through the use of acid and grinding, the unusable thin remnants of true litho-stones were reduced to a pulp to which asphaltum, resin, and oil were added. This mixture was then sprayed onto a zinc plate in a fine even coating. When it had hardened, it could then be drawn upon and processed in a manner fairly typical of traditional lithography.

Postcard

Photochrom: Like many firms, Orell Fussli & Co. established an office in London to help with the distribution of their products. Three tears later in 1896, the Photochrom Company took over Fussli’s London office and began publishing similar postcards after securing the exclusive English license for the Swiss Aäc process. This technique referred to as photochroms was used to produce a great number of view-cards of Europe. While they captured the same fine details as similar Swiss prints, their pallet was much softer and often reduced.

Postcard Detail

Postcard Detail

In 1896 the Photochrom Company took over Fussli’s London office established three years earlier and began publishing similar postcards after securing the exclusive English license for the Swiss photochrom process. This technique was used to produce a great number of view-cards of Europe. While they captured the same fine details as the Swiss prints their pallet was much softer and often reduced.

Postcard

Photochrom: The different color grains used in the Photocrom Company’s photo-chromolithographic postcards tend to be printed in high contrast to one another within any single area. While this created less harmonious color fields it had the effect of uniting the entire composition. This effect was enhanced by using an earthly palette suitable for rendering landscape as seen in the detail below.

Postcard Detail

Phostints
The Detroit Publishing Company obtained an exclusive American license for the Swiss Aäc process in 1897, and by 1903 they began applying their own trade name Phostint to their cards. In some sense they had made these cards their own by constantly experimenting with the process. This tinkering caused their postcard production to undergo a number of technical changes during the company’s history, which in turn continually altered the appearance of their cards, giving them a unique look. Phostints are based on creating a continuous toned lithographic image by directly exposing a negative through contact printing to a stone photosensitized with a coating of Syrian asphaltum. By their careful control of the asphaltum in relation to its processing etch, they were able to manipulate images in countless ways. It is even possible that they may have combined this technique with elements of the Vidal process. While typically six to sixteen litho-stones were employed to print all the different colors needed to create a single Phostint image, many more optical color variations were made possible through their careful alterations of each stone.

Postcard

Phostints: The Phostint process was always being tinkered with resulting in cards with different qualities. Although the early Phostint pictured above was printed from many different stones, a more simple RGB pallet still dominates its color scheme. The card below, printed at least six years later uses much brighter hues and is generally sharper in appearance.

Postcard

There have always been differences in color when any company reprinted their cards because the printing plates were remade from scratch. There was usually great latitude in color choices since these cards were made from black & white photos that were only occasionally accompanied by specific notations regarding the placement of hues. When color is nothing more than a choice, the same choice may not be made twice rendering differences in a card’s printing. Phostints became particularly known for their wild color shifts that could render two or more very different images from the same photograph. While controlled by the technical aspect of the process, the look itself has more to do with decisions made by those handling the processing. By redesigning through alterations in processing, a single photograph could yield many different images. While it was impossible to reprint a card with the same look, The Detroit Publishing Company may have exploited this situation to purposely create variations that would find a wider audience.

Postcard

Phostints: Both the postcard above and the one below were made through the same Phostint process and based on the same photographic negative, yet two very different results were produced. Part of the difference is derived from a change in palette, but more importantly from the way in which each of the stones used were etched.

Postcard

Postcard Detail

Phostint Details: These two details from each of the two cards further up. In the detail above we can see the use of brighter reds but contrast is also darker due to a more dense accumulation of black. In the detail below there is a much heavier use of black throughout the image in the form of a fine grain, which lowers its overall color saturation and helps to unify the image.

Postcard Detail


Postcard

Phostint: Since Phostints were photo-based, it is often easy to forget how extensively retouched they were. In this crowded composition the retoucher left the background nearly flat and colorless to bring our focus to the activity up front. Despite the background’s neutral look, these tones comprise of at least three different hues.


Phostints were often referred to as the Cadillac of postcards because of the fine tonalities, details, and rich color this process was capable of creating. This reference cannot just be considered hyperbole for in an age with little color photography they were able to create images that combined the beauty of an artist’s palette with precise photographic detail. The particulars of their methods were kept such a close trade secret that when Detroit Publishing went out of business in 1932 there were only a handful who knew how to make a Phostint from start to finish. During their last days they fed their furnaces with all written documentation along with leftover cards and working proofs to provide heat for their factory, and the secret techniques they so carefully developed over the years died with them.

Postcard Detail

Phostint: Photo-chromolithographs often give the impression that they capture fine details well, but as we can see from this long detail of a Phostint above, this is only a half-truth. The image is made up of a conglomeration of small markings that are even more irregular in size and shape than found in traditional spatter techniques. Seen close up they do not give a hint of their photographic origin, but they are laid down with such fidelity that a very strong overall photographic resonance remains. This is why these marks can provide definition even without a key plate.


Photochrome Process
In 1935 the Photochrome Process Company was formed by some of the former employees of the defunct Detroit Publishing Company in an attempt to revitalize the Phostint printing process. While they printed postcards until 1940 they were unsuccessful in capturing the look that made the originals so popular. Where the individual markings in Phostints retained sharp edges, Photochrome Process cards have a soft ill-defined look that rendered a similar matte surface as those produced through gravure but without the same richness in tone. Many now refer to the finish of these soft dull cards as frosted to distinguish them from the similar images that were previously printed by Detroit Publishing.

Postcard

Photochrome Process: Memory proved faulty in the absence of documented procedure, and the new Photochrome did not match the vitality of the old Phostint. The dissimilar appearance seems to be mostly due to the different way that the ink sits on the paper.


Poly-Chromes
Poly-Chrome was a trade name used by the American News Company for their screenless photo lithography process. The texture on Poly-chrome cards is similar to that found on Photochroms but they all tend to lack the same fine grain. Their texture in fact is much closer to that of a chromolithograph with a heavier amount of retouching but this is obviously a photo-based process. Poly-chromes can also be more generally characterized as being printed in broader flatter shapes giving them an unnatural look.

Postcard

Poly-Chrome: In this postcard from 1906 large areas of flat tones are used in a manner similar to the Swiss Aäc process but with little of its fine grain. There is much evidence of heavy retouching by hand in the darks as seen in the detail below. This helps to enhance the sharpness of the image.

Postcard Detail


Postcard

Poly-Chrome: When a picture on a Poly-Chrome is broken down into just a few flat fields, its photographic base helps it retain much of its realistic appearance. Sometimes this has more to do with the choice of composition than from any changes in the manner in which it was printed. This postcard was heavily retouched with additions of small flat blots placed underneath the fine photo grain to provide the illusion of fine details that are not there. Even when true details are lacking, the mind’s ability to extrapolate is enhanced when visual information is picked up from the subtleties provided by a photo-based image.


Most Poly-Chrome postcards seem to have been published by the American News Company between 1903 and 1907, but the same trade name and logo can be found on much later cards published by other firms. These late cards however were usually produced in an entirely different technique. A few other publishers produced similar photo based postcards through screenless lithography in combination with traditional drawn techniques. Many such cards were produced in Europe, possibly from the same printing firm without any reference to technique or publisher.

Postcard

Photo-Chromolithograph: This postcard published by Chisholm Brothers makes no reference to technique but it is very similar in appearance to Poly-chromes. While it uses screenless lithography to reproduce its photo-based composition in black and grey, there are also obvious signs of extensive retouching as in the addition of many hand drawn yellow dots.


Photo-Chromolithography
While all the major publishers of photo-chromolithographs are well known, there seems to be many more printers of these types of cards with subtle variations than there are known licensees for. Part of this problem is caused by the large amount of postcards out there that are not attributable to anyone. Most of these types of cards may have simply been contracted out to firms who had the known ability to produce them, but they could very well be the result of other printers who discovered similar methods and put them into production surreptitiously. These methods may be truly unique or they might infringe upon registered patents creating a reluctance to supply attribution. Even when a process is patented, it become difficult to enforce, especially over international boundaries when all parties involved desperately want to hide their trade secrets. Photo-chromolithography was truly one of the Black Arts.


Postcard

Photo-Chromolithograph: While this postcard published by Hugh C. Leighton lacks the varied coloration found on many photo-chromolithographs, its texture is unmistakably makes it one. All cards in this series are characterized by a limited pallet with a dominant orange hue, which gives them a hand drawn look.


Postcard

Photo-Chromolithograph: A good number of photo-chromolithograph postcards were made where there is no reference to publisher or printer as on this Russian postcard. The process however can still be identified as being a photo-chromolithograph by closely examining the clumpy details of the printed grain seen below.

Postcard Detail


Postcard Detail

Photo-Chromolithograph: While photo-chromolithographs are made up of small dots, they tend to be very irregular in shape and size and do not have the same patterning as the hand drawn dots of a chromolithograph even when placed down in a haphazard manner. In both these details above and below we can sense they are more the result of a photomechanical process, but careful observation must be made to filter out this texture from dots drawn in by the hand of retouchers.

Postcard Detail





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