Learn about the development of colour photography—from the very first experiments with hand-colouring to the mass production of commercially viable colour film.
Today we take colour photography for granted. Taking pictures in full, natural colour is so easy that we don’t pause to consider how it all came about. Yet the search for a cheap and simple process of colour photography was a long and difficult quest.
This story explores the different approaches early inventors and entrepreneurs took in the race to develop a successful colour photographic process, from hand-colouring and the Lumière brothers’ autochrome to the first commercially successful ‘integral tripack’ system, Kodachrome.
When was colour first added to photographs?
In 1839, when photographs were seen for the very first time, they were greeted with a sense of wonder. However, this amazement was soon mixed with disappointment. People didn’t understand how a process that could record all aspects of a scene with such exquisite detail could fail so dismally to record its colours. The search immediately began for a means of capturing accurately not only the form but also the colours of nature.
While scientists, photographers, businessmen and experimenters laboured, the public became impatient. Photographers, eager to give their customers what they wanted, soon took the matter, literally, into their own hands and began to add colour to their monochrome images. As the writer of A Guide to Painting Photographic Portraits noted in 1851:
When the photographer has succeeded in obtaining a good likeness, it passes into the artist’s hands, who, with skill and colour, give to it a life-like and natural appearance.
Several different processes and materials were used for hand-colouring, which proved to be a cheaper, simpler alternative to early colour processes. It provided studio employment for miniature painters who had initially felt threatened by the emergence of photography.
In skilled hands, effects of great subtlety and beauty could be achieved. However, even at its very best, hand-colouring remained an unsatisfactory means of recording colour; it could not reproduce the colours of nature exactly.
Photographs could already capture light and shade. What was required was a process that could capture colour in the same way.
The birth of the three-colour process
Before colour could be reproduced, the nature of light—and how we perceive colour—had to be clearly understood.
The scientific investigation of colour began in the 17th century. In 1666, Sir Isaac Newton split sunlight with a prism to show that it was actually a combination of the seven colours of the spectrum.
Nearly 200 years later, in 1861, a young Scottish physicist, James Clerk Maxwell, conducted an experiment to show that all colours can be made by an appropriate mixture of red, green and blue light.
Maxwell made three lantern slides of a tartan ribbon through red, green and blue filters. Using three separate magic lanterns—each equipped with a filter of the same colour the images had been made with—he then projected them onto a screen. When the three images were superimposed together on the screen, they combined to make a full-colour image which was a recognisable reproduction of the original.
Early experiments in colour photography
While the fundamental theory may have been understood, a practical method of colour photography remained elusive.
In 1891 Gabriel Lippmann, a professor of physics at the Sorbonne, demonstrated a colour process which was based on the phenomenon of light interference—the interaction of light waves that produces the brilliant colours you see in soap bubbles. This process won Lippmann a Nobel Prize in 1908 and was marketed commercially for a short time around the turn of the 19th century.
Not long after Maxwell’s 1861 demonstration, a French physicist, Louis Ducos du Hauron, announced a method for creating colour photographs by combining coloured pigments instead of light. Three black-and-white negatives, taken through red, green and blue filters, were used to make three separately dyed images which combined to give a coloured photograph. This method forms the basis of today’s colour processes.
While this work was scientifically important, it was of limited practical value at first. Exposure times were long, and photographic materials sensitive to the whole range of the colour spectrum were not yet available.
The first additive colour photography processes
The first processes for colour photography appeared in the 1890s. Based on the theory demonstrated in the 1860s by James Clerk Maxwell, they reproduced colour by mixing red, green and blue light. These processes are known as ‘additive’ colour processes.
The Kromogram
The American photographer and inventor Frederic Ives devised a system based on three colour-separation negatives taken through coloured filters. From these negatives, positive transparencies were made which were placed in a special viewer, called a Kromskop. Mirrors in the Kromskop superimposed the images on the three transparencies and a second set of filters restored the colours.
Kromograms, as the resulting images were known, were effective but prohibitively expensive, and Ives’ system was, ultimately, too complex to be successful.
The Joly process
Instead of making three separate exposures through red, green and blue filters, a simpler approach was to make just one exposure through a filter that combined all three primary colours.
The first process to use this method was devised by Dr John Joly of Dublin in 1894. Joly covered a glass plate with very fine red, green and blue lines (less than 0.1mm wide) in order to create a three-coloured filter screen.
When taking a photograph, this screen was placed in the camera in front of the plate. After exposure and reversal processing, the black-and-white positive image was carefully placed in register with another filter screen. The result was a colour transparency which could be viewed by transmitted light (light that passes through an object).
The Joly process was introduced commercially in 1895 and remained on the market for a few years. However, the limited colour sensitivity of the plates meant the results were not very successful.
The autochrome
The first properly usable and commercially successful screen process—the autochrome—was invented early in the 20th century by two French brothers, Auguste and Louis Lumière. They had been experimenting with colour photography since the 1890s, and published their first article on the subject in 1895—the same year that they were to achieve lasting fame for their invention of the Cinématographe.
In 1904 they gave the first presentation of their process to the French Academy of Science, and by 1907 they had begun to produce autochrome plates commercially.
News of their discovery soon spread, and examples of the new plates were eagerly sought. The critical reaction was rapturous:
The possibilities of the process seem to be unlimited... soon the world will be color-mad, and Lumière will be responsible.
Alfred Stieglitz, photographer (July 1907)
Realising there was no need to keep the filter screen separate from the photographic emulsion, the Lumières combined both screen and emulsion on the same glass support.
Autochrome gallery
How were autochromes made?
Manufacturing autochrome plates was a complex process. First, pulverised starch grains were passed through a sieve to isolate individual grains between 10–15 microns in diameter. Many different types of starch were tried, but potato starch gave the best results. These microscopic grains were then dyed red, green and blue-violet, mixed and spread over a glass plate, and coated with a sticky varnish.
Next, charcoal powder was spread over the plate to fill any gaps between the coloured starch grains. A roller, using a pressure of five tons per square centimetre, was used to flatten out and spread the grains. The plate was then varnished to make it waterproof.
The final plate was a three-coloured filter screen: there were around four million transparent starch grains on every square inch of it, each grain effectively acting as a coloured filter. The final stage was to coat the plate with a panchromatic emulsion.
How did autochromes work?
Autochrome plates were simple to use. They required no special apparatus and photographers were able to use their existing cameras. Exposure times, however, were long—about 30 times those of conventional plates. Even in bright sunshine, an exposure of at least one second was needed, and in cloudy weather this could be increased to 10 seconds or more. Even in a well-lit studio, portraits could require an exposure of as long as 30 seconds.
Following exposure, autochrome plates were reversal-processed to produce a positive image. When viewed by transmitted light passing through the plate, the millions of tiny red, green and blue-violet grains combined to give a full-colour photograph, accurately reproducing the colours of the original subject.
In theory, the grains were mixed and distributed randomly on the surface of the plate. In practice, however, mathematical probability meant some grouping of grains of the same colour was inevitable. While individual grains are invisible to the naked eye, these groups of clumps are visible; they are the reason for the autochrome’s distinctive beauty and for comparisons with the work of Impressionist and Pointillist painters.
How popular was the autochrome?
By 1913, the Lumière factory in Lyon was producing 6,000 autochrome plates every day.
The commercial success of the process prompted the appearance of many other colour processes based on the concept of screens made up of microscopic colour filters. These screens used either a random grain pattern or, more commonly, different geometric patterns of lines and squares.
Dufaycolor
Many of the photographic processes introduced to the market at this point in history are now long forgotten. However, one remained popular for years: the Dufaycolor process devised by French inventor Louis Dufay.
Dufaycolor first appeared in 1932 as a 16mm cine film, followed in 1935 by a roll film version. It employed a geometric screen made up of red lines alternating with rows of green and blue rectangles. Colour reproduction was good, and it was comparatively fast—although only one-third of the speed of contemporaneous black-and-white film.
Whereas autochromes appealed to keen photographers who liked to do their own processing, Dufaycolor was aimed at the everyday ‘snapshot’ market. A processing service which returned finished transparencies, mounted and ready for viewing, opened up colour photography to a whole new class of photographers.
Dufaycolor, the last of the screen processes, remained on the market up to the 1950s.
Moving from additive to subtractive colour
As outlined above, most early colour photography processes were ‘additive’—they relied on the principle of adding together red, green and blue light.
However, there is an alternative method of reproducing colour photographically: ‘subtractive’ colour synthesis.
What were the drawbacks of additive colour?
Additive colour processes had several disadvantages:
- They relied on the use of filters, which block out light
- This resulted in long exposure times and very dense transparencies
- The colour photographs made using these processes could only be viewed by transmitted light—i.e. by projection or by using special viewing devices
What is subtractive colour reproduction?
The original theory for subtractive colour reproduction can be traced back to the French physicist and inventor Louis Ducos du Hauron, who explained the method in his book Les couleurs en photographie, solution du problème (1869). Du Hauron proposed that colour separation negatives should be used to produce three positive images, which would then be dyed the complementary colours of cyan (bluegreen), magenta (blue-red) and yellow.
Each of these complementary colours absorbs—or subtracts (hence the name)—one of the primary colours. Cyan absorbs red light, reflecting a mixture of blue and green light. A cyan image, therefore, performs the same function as the red filter used in an additive process. Similarly, magenta absorbs green light and yellow absorbs blue light. By accurately superimposing these three complementary colours, all other colours can be reproduced. The colour in subtractive processes comes from dyes or pigments rather than coloured filters.
With subtractive colour, white, for example, is represented by clear glass or white paper rather than by light passing through three filters. This means that subtractive processes are much less wasteful of light.
More importantly, they work with reflected rather than transmitted light, meaning they can be used to produce colour photographs on paper.
How did subtractive colour processes work?
The development of subtractive colour processes followed two distinct paths. Firstly, the design of specialised cameras—for taking sets of colour separation negatives—and secondly, the search for practical methods of making and superimposing three positive images in the complementary colours.
When taking colour separation negatives of stationary subjects—e.g. a vase of flowers—a conventional camera could be used. The colour filter simply needed to be changed after each exposure. This procedure could be made simpler through the use of a ‘repeating back’, a moving part of the camera which allowed filters of different colours to drop into place.
A number of devices of this sort were marketed. The simplest type were long plateholders, fitted with three filters, which the photographer would manually slide along the camera back in three steps. The most complex were fitted with clockwork motors, enabling three negatives to be exposed in rapid succession in as little as two or three seconds.
When photographing subjects where movement was likely to occur—such as portraits—even automatic repeating backs were not fast enough. For these, a camera that could expose all three negatives simultaneously was needed.
Over the years, many designs for such ‘one-shot’ cameras were patented, and a number were produced commercially. These used various arrangements of mirrors and prisms to split the light entering the camera into three separate beams, each of which went to a plateholder fitted with a different coloured filter. Among the most successful designs were the Jos-Pe, Bermpohl, Klein and Mirkut cameras.
Carbon printing
Obtaining satisfactory negatives was just the first stage. These negatives then needed to be converted into positive images in the complementary colours of cyan, magenta and yellow.
Several different methods were used to obtain these images, the most popular being variations of the carbon process. These used sheets of carbon tissue, consisting of a gelatine coating, containing pigment, on a paper base. The tissue was sensitised before use by soaking it in potassium bichromate. Potassium bichromate hardens when
exposed to light so, after exposure in contact with a negative, the areas of unhardened gelatine could be washed away to reveal an image.
Tissues could be produced using pigments of any colour; images on cyan, magenta and yellow tissues were then superimposed to produce subtractive colour prints.
A variant of the carbon process was the Trichrome Carbro process. It used a set of bromide prints made from separation negatives to make the necessary yellow, magenta and cyan pigment images on tissue for transfer in sequence on to a paper base. The process was first developed during the 1890s but made popular by the Autotype Company of Ealing during the 1920s and 1930s.
While processes such as Carbro were available for amateur photographers to use, tissue assembly techniques were difficult and complex. Apart from the really dedicated, most amateurs preferred to use additive processes such as the autochrome process and Dufaycolor.
The Vivex process
During the 1930s, commercial colour photography became increasingly important. For professional colour printing, at this time, one process reigned supreme: Vivex.
Invented in 1928 by Dr Douglas A. Spencer, who later went on to become Managing Director of Kodak, Vivex was a modification of the Trichrome Carbro process in which sheets of cellophane were used as temporary supports for the pigment images. Any minor problems with the image could be corrected manually by stretching or squeezing the cellophane to ensure perfect superimposition.
To exploit the Vivex process, a company called Colour Photographs (British & Foreign) Ltd. was formed with a factory in Willesden, north London. This was the first laboratory to offer a colour print making service to professional photographers.
Such was the popularity of the Vivex process that it has been estimated that over 90% of all the colour prints made in Britain in the 1930s were produced using it.
Vivex gallery
The tripack system
Subtractive colour processes, such as Vivex, required colour separation negatives to be made on three separate photographic plates. However, if all three could be combined into a single unit—or tripack—there would be no need for specialised colour cameras or repeating backs fitted with filters.
It was the invention of tripacks that paved the way for the development of ‘modern’ colour processes such as Kodachrome.
What was the tripack system?
The basic idea of the tripack system was to construct a multi-layer unit, where each plate was coated with an emulsion sensitive to one of the primary colours. Light would pass through the first plate in order to reach the second emulsion layer and, in turn, pass through that plate to register on the third emulsion.
The first practical tripack system was introduced by Frederic Ives, an American inventor, in 1916. His ‘Hiblock’ tripack consisted of a sheet of film sandwiched between two glass plates. The top plate was blue-sensitive, the film was green-sensitive and the bottom plate was sensitive to red light. After exposure, the three layers were separated for processing; the negatives were then treated as conventional separation negatives.
After Ives’ invention, other tripack systems followed, including one that turned out to be a famous failure: the Colorsnap process.
What was the Colorsnap process and why did it fail?
The late 1920s was a time of great technological change in the western world: as well as photography, new inventions such as the gramophone, radio and cinema were rapidly growing in popularity. As a result, there was a frenzy of investment in companies promoting new innovations.
One such company was the London-based Colour Snapshots Ltd., established in 1928 to promote a tripack photographic process called Colorsnap. It was set up with massive financial backing and invested heavily in promoting its competitively priced products.
However, despite extravagant claims, the results were disappointing. The negatives from the second and third emulsion layers were so blurry that the company was reduced to hand-colour black-and-white prints made from the sharpest (front) element of the tripack. Unsurprisingly, Colour Snapshots Ltd went bankrupt in December 1929.
The Colorsnap process suffered from the same problem inherent to all tripack systems. Light was scattered and diffused as it passed through the various layers of emulsion, so one or more of the resulting negatives were blurred. Definition was too poor to allow much enlargement; tripack negatives were usually only recommended for contact printing.
Solving the problems of the tripack system
The tripack system was quicker than previous colour photography processes, but resulted in blurry negatives. The solution to this problem was to coat all three emulsions onto the same glass or film support. This was called an ‘integral tripack’. Since it was physically impossible to separate the layers, each had to be capable of being chemically processed in isolation so as to produce an image in cyan, magenta or yellow.
In 1912, Rudolph Fischer had patented a proposal to use what later became known as ‘colour couplers’—substances that react with chemicals formed during development to create coloured dyes. Fischer suggested that colour couplers for producing cyan, magenta and yellow dyes should be incorporated into the appropriate layers of an integral tripack so that coloured images would be formed during development. The result would be a full colour photographic image.
Unfortunately, the colour couplers Fischer used tended to disperse between emulsion layers during processing. Fischer’s theory, however, was sound, and his work was to form the basis of the research that led to the first commercially successful integral tripack system—Kodachrome.
The invention of Kodachrome
Kodachrome was the invention of Leopold Mannes and Leopold Godowsky. Both earned their living as professional musicians (Mannes played the piano and Godowsky the violin) while spending their spare time experimenting with colour photography. Despite their best efforts, there came a point when they were unable to progress without outside support.
This support was to come from Dr C.E. Kenneth Mees, director of the Eastman Kodak research laboratories in Rochester, New York. In 1922, Mees met with Mannes and Godowsky and, impressed with the quality of their work, agreed to supply them with the materials they needed to continue their research. At this point, they were working on a two-colour subtractive system for colour photography but, after reading about Fischer’s work with colour couplers, they decided to abandon their previous methods and concentrate on developing a three-colour multi-layer film system.
In 1931, the two Leopolds gave up their musical careers to work full-time in the Kodak research laboratories where, with the help of Eastman Kodak’s enormous resources, they made rapid progress.
How did Kodachrome work?
Like Fischer, Mannes and Godowsky had great difficulty in preventing the coloured dyes spreading between the emulsion layers. They overcame this by putting the colour couplers in the developer rather than the emulsion.
Kodachrome is, in effect, a black-and-white film to which coloured dyes are added during processing.
Kodachrome processing—imvolving repeated development, dyeing and then selective bleaching—was extremely complex. In all, it required at least 28 different stages that could only be carried out in laboratory conditions.
For this reason, photographers were unable to process their own film; they had to send it back to the Eastman Kodak laboratories in Rochester.
When did Kodachrome film first go on sale?
On 15 April 1935, the first Kodachrome film went on sale for use in 16mm cine cameras. 35mm Kodachrome film was available on the American market in 1936, and the first supplies reached the UK in 1937.
Agfacolor-Neu
In 1936, Agfa, a German company, also announced a multi-layer colour film.
Agfa had been making additive colour plates since 1916, so they called their colour film Agfacolor-Neu—‘new’ to indicate that it was completely different from any earlier products. Agfacolor-Neu was the first commercial process to follow Rudolph Fischer’s theory of using colour couplers.
Agfa’s research chemists discovered a way of anchoring couplers in the individual emulsion layers. This made Agfacolor film much easier to process. Unlike Kodachrome, it could even be done by the user at home.
After the Second World War, the details of Agfa’s research became freely available, and other companies—such as Ferraniacolor and Gevacolor—introduced colour film based on the same principle.
With the perfection of dye-based multi-layer colour films such as Kodachrome and Agfacolor-Neu, a new era of colour photography had dawned. The quest for colour—a search that had begun with the invention of photography nearly 100 years earlier—was over.
Further reading
Online
- The history of photography in pictures, National Science and Media Museum
- Autochromes: the dawn of colour photography, National Science and Media Museum blog
- A brief history of Kodachrome, Claire Suddath, TIME
Books
- Brian Coe, Colour Photography: The First Hundred Years, 1978
- Jack H Coote, The Illustrated History of Colour Photography, 1993
- Joseph S. Friedman, History of Color Photography, 1945
- Pamela Roberts, A Century of Colour Photography, 2007
- E.J. Wall, The History of Three-Color Photography, 1970
- John Wood, The Art of the Autochrome: The Birth of Color Photography, 1993
- John Wood, ‘The Art of the Autochrome: A supplemental bibliography’, History of Photography, Summer 1994