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Photography and the Black Arts


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TRANSFER PROCESSES


Today we largely view the making of photographic prints and the printing of photo reproductions as two very different entities, but in their infancy these distinctions were far less clear. They were both tools of the graphic arts and early efforts to mass produce photographic images would lead to discoveries in multiple mediums that would eventually have an impact on all methods of reproduction. Methods of transferring images between mediums became an all consuming quest. Nothing was to play a more important role in this than the development of gelatin tissue for it greatly expanded the printing trades ability to reproduce photography. Likewise more simple mechanical transfer methods would also make the work of artists and retouchers more efficient. The impedes behind all this was a constant effort to reduce labor cost; and by incorporating photography into printing, many hours of skilled work could be removed from the process. Photography was just one element, though an important one in the trend to move printintmaking away from artists to craftsmen to laborers and finally to machines.

Carbon Prints and Gelatin Tissue
In 1855 Alphonse Louis Potevin elaborated on the gum printing process and found a new way of reproducing photographic images. These carbon prints were made by the triple transfer of a photographic image onto gelatin emulsions. In this process three pieces of paper are coated with a photosensitive gelatin emulsion containing carbon powder. The first sheet is exposed to a negative and developed out with water. It is then positioned emulsion to emulsion with a second sheet of hardened gelatin, and pressed together into one piece. The paper from the first sheet is then removed. This thin gelatin film is called carbon tissue. The areas on it exposed to light have hardened while the remaining gelatin has washed away. With the fully exposed areas now attached to the second sheet of paper, the remaining mid-tones and highlights tend to wash off producing an image with poor tonal range. Since this image was transferred from one tissue to another it is now in reverse, and must be transferred by the same process to the third emulsion to regain the correct orientation. This method would be improved upon by many others such as John Pouncy in 1858, but the basic principals remained the same.

Joseph Wilson Swan took carbon printing a step further by adjusting the transfer process. The gelatin emulsion photosensitized with potassium dichromate was now only washed after the first transfer and from the opposite side thus preserving more of the original detail. An alum bath would then be used to harden the remaining gelatin. This new type of emulsion was known as gelatin tissue, which Swan patented in 1864. The photographic prints created through these improvements display a much wider and richer tonal range than the original process. Substituting various pigments for black carbon could also change the color of the final print. Because no silver is used, these photographs are known for their permanence and were made in large numbers until 1910.

Gelatin tissue had wider implications for the printing trades. After being exposed to light through a transparency the tissue could be adhered to a printing substrate using alcohol. When its paper backing is removed, only a thin gelatin membrane (tissue) is left behind. The unexposed gelatin can now be washed out with water leaving behind a hard gelatin relief that acts as a resist to the following etch in proportion to its exposure to light. Since exposures could only be made with sunlight during the early years of printing, this new tissue that could be exposed independently of the substrate became indispensable for the transferring images onto difficult surfaces such as heavy litho-stones and large rotary cylinders. In many ways it was a revolutionary innovation that greatly expanded the use of both lithography and gravure. A version of this tissue that could be dried and stored was made commercially available two years after its initial invention. The Autochrome Printing & Publishing Company bought the rights to this product in 1886. Gelatin tissue is so closely based on Potevin’s earlier carbon tissue it is often incorrectly referred to by the same name.

Woodburytype (Photoglyptie)
In 1864 Walter Bentley Woodbury patented an early method of creating a printed image almost identical to that of a photograph. It was an attempt to solve the problem of fading while bypassing the chemistry of processing silver nitrates. The method is based on carbon photography only here it is carbon tissue photosensitized with a dichromate that is exposed to a negative. The areas exposed to light harden in proportion to their exposure, and when the remaining gelatin is washed out, a very shallow relief is left behind. This hardened relief is then pushed into a sheet of soft lead with a hydraulic press under great pressure. The result is an intaglio printing plate, but instead of inking it a solution of warm pigmented gelatin is poured into it as if it were a mold. A sheet of paper is then placed on top while still wet and pressure is applied. As the solution cools the image is transferred onto the paper to which it binds. Even though the gelatin will shrink as it dries, the finished image still needs to be trimmed off at the edges to rid itself of excess gelatin. Since woodbutytypes consist of a carbon gelatin cast and not ink they are nearly identical in appearance to carbon photographs.

Woodburytype Postcard

Woodburytype: The woodburytype process was so complicated that it was very rarely used in the production of postcards. When found they usually take the form of fine portraiture. Any color pigment could be added to the gelatin solution but most prints have a brownish cast to resemble albumen photographs.


The delicate plate used to make woodburytypes could only yield about 100 prints. It was a very complex and expensive reproductive method and woodburytypes were usually only used in high quality books as tip-ins, though they do appear on cabinet cards. Its use ended around 1900 as other methods more adaptable to commercial printing were developed. While this process was generally too expensive to be used in the production of postcards it was later combined with lithographic techniques that were more commercially successful, such as photochromie. Photo collage was a popular 19th century pastime where images taken from many photo sources were cut up and pasted into scrapbooks together with drawings and other printed material. This collage tradition was carried over to early postcards, especially of the handmade variety where pieces of early tintypes, albumen prints, and woodburytypes might sometimes be found.

Stannotype
The stannotype process was a variation of the woodburytype. Although it began the same way by exposing a sheet of gelatin tissue to a negative, tinfoil would then be pressed directly into the gelatin instead of the gelatin being pressed into lead. Sometimes a rubber cast would first be made of the shallow gelatin relief into which the tinfoil was pressed. The tinfoil, now transformed into an identical relief would then be electroplated and mounted on resin to give it extra strength before it is used to cast a finished print in pigmented gelatin. There were a number of similar processes in use at the same time such as the dallastype dating from 1864 that used a plaster cast.

Transfer Lithography
In the early 1800’s, methods of transferring a drawing from a sheet of paper to a litho-stone were developed so that the double transfer would result in a final print that was not mirrored but oriented to the original. This was imperative when printing text, but because there is always some loss of fine detail when transferring an image the direct method of drawing on a stone remained the most popular. Even so, transfer paper offered artists the opportunity to work away from the poorly portable stone, and the drawing could also be more heavily manipulated with scratching and abrasion without disturbing the stone’s fine polished grain.

While small areas of a stone can be repolished with hand tools, there was really no good way to erase mistakes made in a lithographic drawing without potentially damaging the stone’s surface. If serious mistakes were made on a stone, it would have to be reground while transfer paper could just easily be discarded. Metal litho-plates that had no depth, could not take any sort of correction, and so it became common to transfer drawings onto them Many artists also believed that the transfer process worked better on metal. There was a great variety of transfer papers available to meet any task at hand. Most were usually coated with some sort of water-soluble gelatin or gum and then drawn upon with the same greasy crayons, tusche or autographic ink normally used in lithography. These thin papers could also be placed over a rough surface as if making a rubbing to impart patterns or texture into a drawing. Once moistened and pressed face down on a stone or plate, the blackened grease would stick and the gelatin and paper could be washed away. Uncoated papers were also available but there was an even a greater chance of image loss when using them, especially in the finer details.

Printers often had difficulty meeting the growing demand for lithographic prints in the early 19th century. This was most often true when an image captured a newsworthy or sensational event that the public had a great appetite for. It was found that production could be greatly increased by using the transfer process to create additional stones that could print the same image. Once the drawing on the initial keystone was made and processed it would be rolled with a greasier transfer ink made specifically for transfer and printed. This wet print would then be laid upon another prepared stone and the image was then transferred to it with pressure. Once processed there would be two stones capable of printing images identical in every way except for the random stone grain. This process could be repeated over and over until a printer had all the stones needed for the job. Since any image drawn on stone will slowly deteriorate as it is printed, transfers were often made before a press run began to insure a second stone would be readily available to complete the job if the first stone wore out.

Postcard

Facsimile Woodcut: Although this postcard clearly depicts a woodcut, there is some doubt to whether it was printed as such or if it is really a line block. Within the whites there are more specs of black than would usually show up in a woodcut that are typical of accidental spatter on a line block plate. While it is possible that this image was drawn in a woodblock style there are many nuances that are very typical of knife cutting such as the white line around the figures. This may indicate the existence of an original woodcut that was printed on transfer paper, and then transferred to a metal plate to print as line block, but there is no way to know for sure.


Ink-Photo
Transfer paper was easily applied to intaglio plates including those used for line block printing where the ink acted as a resist to an etch. A more unusual use for this paper was in the transfer of collotypes to litho-stones. Around 1885 Sprague & Company developed a method to create such a print they termed Ink-Photo. The problem inherent in this process was in matching the fine grain of the collotype up with the fine grain of the litho-stone. To help solve this mismatch, a thicker gelatin emulsion that produced a much coarser reticulated surface was put into use. While this adjustment sill created a random series of markings, the enlarged scale interfered with the fidelity of details and the prints lost the delicacy of tone associated with collotypes. Although printing an image as a lithograph was more cost effective printing one as a collotype, this transfer method saw little use as it suddenly found itself in stiff competition with halftone line blocks. The ink-photo process however would find another use in creating transparencies for random mezzograph screens used in photomechanical printing. Since images are adhered to transfer paper and transparent screens in the same manner, it is almost impossible to determine by which method a card is made, but it is likely that most of these types of postcards were made through a screen.

Postcard

Ink-Photo: By the time postcards came into production few printers were still making ink-photos. Their legacy however continued in the photomechanical prints made through mezzograph screens. It is impossible to tell by which process this rare English card from 1931 was made due to the similarity in outcomes. The enlargement below takes on the appearance of a tinted collotype, but in the greater enlargement further below the coarser reticulated pattern becomes evident; it is about ten times larger than found in the average collotype.

Postcard Detail

Postcard Detail


Decalcomania
Decalcomania (decals), whose origin is often credited to the French engraver Francois Ravernet was a process first developed in England during the 1750Ős that allowed surfaces that could not be printed upon such as ceramics to receive printed designs. The basic principal was that the ink used for transfer had to be attracted to its new home more than the original surface it was printed on. This transfer was usually aided with the help of water, heat, or pressure. Decalcomania arrived in the United States in 1865 where the designs were most often printed on transfer paper through lithography. Though originally designed for application on unusual surfaces, they eventually became a part of the normal printing process and were extensively used by retouchers in the production of postcards.

Decal

Decal: This old decal was printed on gummed paper with three color line block plates.


Retouchers spent so much time polishing out unwanted details and adding in new desired elements that they began using decals to speed up their work. These tiny images of people, cars, and boats could be purchased or manufactured in house. Many printing firms had these details drawn onto stones by there own artists that were then printed onto gummed transfer paper and stored as stock images. When a new composition required a car or person absent in the original image, the retoucher could just go to a cabinet, remove the appropriate sheet, and cut out what he needed. If these decals were printed with a greasy transfer ink they could be directly applied to a polished stone, but if they were made with regular printing ink they were pasted onto a transparency before it was exposed to a photosensitive substrate. Unfortunately the size of the decal dictated its exact placement on the picture plane, and a distorted image would result if this rule was not followed.

Postcard

Decal Retouching: The use of a decals can often be detected because of a problem with spacial scale. Here on the card above, the car has been placed too low on the picture plane in relation to its size within an otherwise photographically correct image making it look like a toy. Decals required exact placement since their size could not be altered, but this did not always match up with compositional concerns and they were often positioned incorrectly. Another clue to finding decals is when the same detail shows up in the composition of different postcards.



SHADING MEDIUMS


Paper Grains (Paper Tints)
Even though lithography and line block are only capable of printing a single tonal value at a time, a much wider range of values is achievable through optical blending. This effect of course can be created by handwork but it is a tedious process when trying to render large fields of even unbroken tone. A number of special grained papers were designed to aid this process in order to speed up production. The most common of these was a heavy white paper embossed with a patterned field of dots on which the artist would draw with a black crayon. The black pigment had a tendency to only stick to the top of the dots but they could grow larger and the tone darker as more pressure was applied with the hand, similar in principal to making a rubbing. Other papers had thin ridges embossed into them, which when drawn yielded an image rendered in a series of varying lines. These lines were supposed to simulate those achieved through engraving, but the resemblance is tenuous at best. An artist could manipulate these grained papers in various ways with the nuance of his hand. When photographed and transferred to a substrate, the printed image would retain the value structure of an actual drawing even though created through small optical markings. Transfer papers would eventually be made with similar patterns already manufactured into them.

Postcard Detail

Paper Tints: Both these printed textures were made through the use of paper grains. The detail above shows a line pattern transferred onto a line block printing plate, and on the bottom is a detail of a tinted pattern printed in lithography.

Postcard Detail


Postcard

Paper Tinted Lithograph: The image on this lithographic postcard is created with drawn dots, blots, and paper tints. The tints used here are all on the same rotation creating optical colors and softening contrast. It is often difficult to discern how patterned dots were created but those with a coarse and somewhat irregular shape as seen below are usually the result of drawing on top of a paper tint.

Postcard Detail


Postcard

Paper Tinted Lithograph: The image on this lithographic postcard is created with drawn dots, blots, and paper tints. The tints used here are all on the same rotation creating optical colors and softening contrast. It is often difficult to discern how patterned dots were created but those with a coarse and somewhat irregular shape as seen below are usually the result of drawing on top of a paper tint.

Postcard Detail


Postcard

Paper Tinted Lithograph: This lithographic postcard from 1915 has the drawn feel of a crayon, but on closer examination its texture is too coarse to come from a polished stone. In the detail below we can see that the black key printed over color dots was drawn with the aid of a paper grain. It has the telltale markings of dots run together in the shape of X’s and Z’s created by the heavy application of pressure of the artists hand.

Postcard Detail


Postcard

Paper Tinted Lithograph: The unusual postcard above was drawn entirely with linear paper grains. This technique closely resembles the effect often found in chromoxylographs when the blocks were cut as lines. In the detail below we can see that each color was rotate, even though put in through lines rather than dots. Despite this effort, an interference pattern is still created most evidenced in the sky when digitally scanned.

Postcard Detail

Because of the wide variety of paper tints used, it is not always easy to discover their use on a printed image. Some tinted papers were made with the peaks of all dots already blackened. The artist could then blacken them further with crayon or fill in the spaces between them entirely with ink. This heavy paper could also be scraped so that preexisting black dots could be removed to print solid whites. Scrapping paper however is not like working with metal or stone and the results on this soft surface can produced poor tonal transitions. Images originally created with paper tints were sometimes reprinted in a new medium through the use of transfer paper or by photomechanical means. Poor translations between the dot patterns of one medium to another could distort the characteristics of the original drawing.

Shading Mediums (Manufactured Tints)
We are so familiar with photographic halftone images today that we think of little else when finding patterns of dots on a postcard. Many cards however employed a process invented in 1879 by the New York printer Benjamin Day. He produced film sheets embossed with a pattern that could be rolled up with a greasy transfer ink, and then conveyed to a litho-stone. The transparency of these sheets allowed the retoucher to see where the pattern needed to be laid guided by the chalk drawing underneath. By applying localized pressure to the back of the film, the ink could be transferred to the desired areas either evenly or in varying degrees of intensity. While Day produced over a hundred different printable designs, it was his dot patterns (benday dots) that were the most popular. These dots spaced at regular intervals produced completely even tones, and by varying the dot size or using sheets made in varying frequencies an entire range of values could be produced.

Postcard Detail

Benday: The detail above shows a typical benday pattern printed in lithography that was used to fill in a sky. The red benday pattern on the line block below was used throughout the image to add a warm color cast.

Postcard Detail

An important use of benday patterns was to increase the appearance of optical colors when only a limited palette was used for printing. Dots of one color could be laid over a solid field of another or dots printed in two colors could intermingle. Though similar in methodology to four color process printing, there were no photographic separations of color used on these postcards; all placement was done by the discretion of the retoucher. The amount of color variations that could be created with this method was only limited by the dot pattern itself. Too many overlapping dots however could add new and unsightly interference patterns (moiré) to the image. Two layers of dots could sometimes succeeded if the colors used were pale or when they were printed nearly over one another.

Postcard

Benday: All the color on this postcard is created through red benday patterns of varying weight. They were then overprinted with a halftone key in black.


Even after line blocks began to be made with photographic halftones, the use of shading mediums did not end. Benday was often an essential component of retouching work used to add tone or color back into a drawing. The tonal values of color are largely determined by the ink chosen, not the image on printing substrate, so areas that will print lightly still need to have a strong presence on a plate. Even a mark that will print white is first drawn in as a black. It is in areas such as the sky that details are most often absent when made from high contrast black & white photographs, and so they are placed back into the composition with shading mediums. Parts that needed to be given stronger color emphasis can also be added in this manner. The dots would print the same color as that of the rest of the plate they were added to. At first glance benday dots can easily be mistaken for a halftone screen pattern, especially when both are used on the same plate. When observed more closely, the density of benday dots tend not to change except for slight variances due to the pressure of application. They may grow blotchy as they get bigger but they will never form an optical bump that creates the checkered pattern so often found in halftones. They do however closely resemble paper tints, and they cannot always be told apart.

Postcard

Benday and Lithography: It is important not to underestimate the ability of a retoucher to create a photo like picture entirely through the manipulation of shading mediums. The image on this postcard consists entirely of lithographic spatter overprinted with multiple colors of benday dots. Though the dots are all printed with identical rotation, moiré patterns are averted due to their very small size and high density tempered by the irregular laid dots beneath them. While a strong looking screen pattern is create, it is only visible under magnification as seen in the detail below. Many printers used benday extensively to render images on postcards.

Postcard Detail


Postcard

Benday and Lithography: This seemingly simple postcard was printed in eight colors, with two sets of reds, blues, browns, and a yellow. While the color was applied in broad flat areas, the deep brown used on the key plate is entirely made up of benday dots. They first take on the appearance of a halftone but their shape as seen in the detail below are just too irregular to be formed by a line screen.

Postcard Detail


Postcard

Benday and Lithography: he Japanese card above does an excellent job in hiding the fact that it is completely made up of benday dots. The dots that comprise the blue, red, and black are laid down so close together that they practically form a solid blot. Yellow is carefully infused with black dots to create subtle shifts in the gold-like tone. In the detail below we can see that the cardŐs highly segregated flat colors are only an illusion as multiple colors are really integrated.

Postcard Detail


Postcard

Benday and Collotype: Lightly printed lithographic dots were often used as tints underneath collotypes as the irregular hand drawn pattern did not distract from its continuous tone. In the rare case of the German card above, all the color is created through benday dots alone, which are distributed throughout the entire image. Though applied with varying pressure to change tonalities, its regular pattern is clearly visible in the detail below.

Postcard Detail


Postcard

Benday and Line Block: Hand drawn line work is used on this early line block postcard to create the figures and outlines while shading mediums were used to create tone. The dot and line patterns in the detail below seem too irregular to have been created by a mechanical tint but their frequency falls at totally measured intervals suggesting that they were not drawn in by hand. The most obvious conclusion is that they are a result of manufactured tints pressed onto the printing plate.

Postcard Detail

Mechanical Tints
Sheets of mechanical tints representing a full range of values that could be cut up and directly added to drawings or transparencies before the image was exposed to a photo sensitized plate eventually became widely available. To speed up production artists would often only make notations of where tones or color needed to be placed along with their relative density, and it was then up to the retoucher to select the corresponding tint, cut it to size, and paste it onto the negative. Mechanical tints were mostly used on postcards that contained simple illustration or combinations of photographic halftones with graphic design. While these patterned sheets were made by a variety of different manufacturers, they and the dots they produced were all commonly miscalled benday.

Postcard

Mechanical Tint and Halftone: The montaged images on this multi-view postcard were printed in halftone, but the colored spaces in between were filled in with mechanical dots. A slight overlap was calculated in to the composition to avoid white lines if they were not printed in perfect register.

Postcard Detail





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