“Polychromide (1918), a two-colour subtractive synthesis process, patented in England by Aron Hamburger. The positive film bore emulsion on both sides (bipack), and was printed with two different negatives, one orthochromatic, the other panchromatic (a subsequent patent substituted a single bipack negative for these), then toned red-orange on one side and blue-green on the other.”
(Cherchi Usai, Paolo (2000): Silent Cinema. London: BFI, p. 36.)
“Der Gummidruck wurde von Prof. Miethe 1903 in einem eigenen Farbbildprozeß mit der Cyanotypie kombiniert, wodurch Miethes bedeutungsloses Verfahren zu einer Reihe teilweise beachtenswerter Methoden gehört, die verfahrenstechnisch eine Zwitterstellung einnehmen. Diese 1888-1930, also von Ives’ Heliochromy bis zu einem Vorläufer von Vivex ausgeübten Verfahren benutzten für das Blau-Teilbild alle die seit 1842 bekannte Cyanotypie. Damals entdeckte Sir John Herschel, daß sich ein mit Eisensalz und Kaliumferricyanid behandeltes Papier nach Lichteinwirkung blau färbte. Als Verfahren, die die Cyanotypie für das Blaubild benutzten, sind hier noch Sanger-Shepherd und sein deutscher Nachahmer Dr. Hesekiel (1899) sowie Ives’ Hi-Cro Color Process für Papierbilder (1915) zu nennen; sie arbeiteten für die anderen Teilbilder mit nachträglich eingefärbten Auswaschreliefs. Ferner gehört hierhin eine größere Gruppe von Prozessen, in denen die Cyanotypie mit der damit verwandten Tonung kombiniert war. Zu letzterer zählte u.a. Aron Hamburgers 1911-1913 in den Londoner Dover Street Studios ausgeübtes Polychromide-Verfahren. Dieses Porträtatelier arbeitete schon recht modern: Unter dem Licht starker Blitzlampen könnten die Aufnahmen mit einer eigenen, von Otto Pfenniger, Brighton, konstruierten Strahlenteilerkamera mit 1/100 Sek. bei Blende 6,3 gemacht werden.”
(Koshofer, Gert (1981): Geschichte der Farbverfahren in der Spezialistenzeit. In: Joseph-Haubrich-Kunsthalle and Agfa-Gevaert Foto-Historama Leverkusen (eds.): Farbe im Photo. Die Geschichte der Farbenphotographie von 1861 bis 1981. Katalogbuch. Köln: Joseph-Haubrich-Kunsthalle, p. 101. (in German)
“Polychromide, a two-color subtractive process invented in 1918 by Aron Hamburger, achieved limited commercial success overseas, and was occasionally employed in England as late as 1933. Originally an orthochromatic and a panchromatic negative were exposed in a beamsplitter camera. Later the use of the beam-splitter was dropped in favor of a conventional camera using bipack negative films. Polychromide prints were made on double-coated positive film stock which was dye toned red-orange on one side and blue-green on the other. Exposure from each of the camera negatives was made simultaneously by the printer on opposite sides of the positive film. Perhaps the most significant advancements made by Hamburger lay in his dye-mordanting process. He was probably the first to dye the film first and to bleach and mordant afterward. This alteration of standard procedure resulted in improved color consistency throughout the length of the film.8
Although Hamburger was an American by birth, he developed his system in England and no record of its commercial use in the United States could be found.
8 Hal Hall and William Stull, “Motion Pictures in Natural Colors,” in Cinematographic Annual–1930, The American Society of Cinematographers Hollywood: The Hartwell Publishing Corp., 1930), p. 277.”
(Nowotny, Robert A. (1983): The Way of All Flesh Tones. A History of Color Motion Picture Processes, 1895-1929. New York: Garland Pub, pp. 132-133.)
“The Polychromide process was a two-color subtractive system of color cinematography invented in 1918 by Aron Hamburger. While this process was invented by an American, it cannot truly be called an American process since it was developed and used commercially in England rather than the United States.19
For this process an orthochromatic and a panchromatic negative were exposed in a beam splitter camera. With the introduction of Bi-Pack negatives the use of a beam splitter camera was dropped in favor of conventional cameras and Bi-Pack negative films. After exposure the negatives were processed in a normal black and white developer, fixed, washed and dried. Prints were made on double coated positive film which was dye toned red-orange on one side and blue-green on the other side. Hamburger claimed that the dye mixture he used had special properties when applied to a photographic image. With his two-color process he claimed to reproduce foliage as green and the sky as purplish blue. Yellows were reproduced due to the addition of auramine to the magenta dye.
Polychromide prints were made on a Debrie printer which exposed both sides of the positive film simultaneously. After exposure a low density, low contrast image on both sides of the film was developed by immersion in a metol developer. Next the dye was applied to each side separately by a series of application wheels. The side printed from the orthochromatic negative was dyed with a mixture of Fuchsin and Auramine. The side printed from the panchromatic negative was dyed with a mixture of Malachite Green and Helio Safranine. Dyeing was followed by immersion into a combination bleach and mordant, then into a clearing bath, followed by a wash and drying. According to Cornwell-Clyne, the use of the dye first followed by the bleach and mordant resulted in a considerable gain in overall evenness in the process.20
19 CORNWELL-CLYNE, Cinematography (London: Ltd., 1951), p. 19.
20 Ibid., p. 340.”
(Ryan, Roderick T. (1977): A History of Motion Picture Color Technology. London: Focal Press, pp 75-77.)
“Only a few three-color toning processes have been released commercially. These include Polychromide by Hamburger in about 1923 (Wall, 1925, pp. 401-402; Friedman, 1944, p. 307), Triadochrome by Shepherd (Wall, 1925, p. 402), and Chromatone by Defender Photo Supply, Inc., about 1936 (Friedman, 1944, pp. 319-322). Several two-color toning processes have been used in motion pictures, among the best known being Multicolor and its successor Cinecolor.
Friedman, Joseph S., 1944. History of Color Photography. Boston: The American Photographic Publishing Co. 514 pp.
Wall, E. J., 1925. The History of Three-Color Photography. Boston: American Photographic Publishing Co. 747 pp.”
(Evans, Ralph Merrill / Hanson, W.T., Jr. / Brewer, W. Lyle (1953): Principles of Color Photography. New York: Wiley, p. 296.)
“Aaron Hamburger’s successful Polychromide process for still photography, operated in England from 1911, was adapted by him for cine work around 1918. It was demonstrated under the name Veracolor in 1924, but was better known under its original name. A special camera with a beamsplitter behind the lens exposed two negative films through red and green filters. As usual, the developed negatives were printed onto opposite sides of double coated film, which was exposed and processed to give a rather ‘thin’ black and white image. Each side of the film was dyed with a mixture of dyes – magenta and red on one side, malachite green and blue on the other. Treatment in a mordanting bath fixed the dyes in the film only where there was a silver image, and in proportion to it. Hamburger claimed that the use of mixtures of dyes gave a wider colour range. The Polychromide process was used into the middle 1930s, although only for short films.”
(Coe, Brian (1981): The History of Movie Photography. Westfield, N.J.: Eastview Editions, p. 128.)
“Another early example of two-color film process was the polychromide by Aaron Hamburger, a London photographer. He experimentally introduced his process in 1928. Hamburger was well-known for his three-color photography process, also called Polychromide, used from 1911 to 1913 in the Dover Street Studios in London for fine portraiture work.”
(Koshofer, Gert (1996): Early Colorfilm Processes for the Cinema. In: Monica Dall’Asta, Guglielmo Pescatore and Leonardo Quaresima (eds.): Il colore nel cinema muto. Bologna: Clueb, pp. 43-44.)
“This process was developed in England by the late Aron Hamburger, whose name was originally brought into prominence by his portrait photography in colours for which he had established a studio in London before the War. He had taken out certain patents for still-colour cameras, and toning processes (E.P. 28,722,1912, A. E. Conradi and A. Hamburger; and E.P. 20,880, 1911). The former patent describes means for applying distortion to a reflector by the application of pressure on different points around the edges, in order to correct for the unequal distortion produced in the transmitted image when a plain reflector is used. The latter patent was for toning a print yellow by means of mercuric chloride and potassium iodide, of which formula Hamburger always claimed to be the originator. Later, in 1918, appears a patent (E.P. 136,595, 1918, A. Hamburger and W. E. L. Day) in which is described a beam-splitter camera for motion pictures with two gates at right angles to each other, and a reflector similar to that described in Specification 28,722, 1912. In E.P. 203,358, 1922, is described the method of dye-toning which ultimately became known as the “Polychromide” process. He describes the method of exposing an orthochromatic film sensitized with erythrosine and a panchromatic film sensitized with pinacyanol. These two films were exposed in the Hamburger beam-splitter camera. Positive prints are made from these on the opposite sides of double-coated positive film. A mixture of Rhodamine B and Auramine is then applied to the positive printed from the orthochromatic film, and a mixture of Malachite green, and one of the basic blue dyes, to the positive printed from the panchromatic film. The positive film is then bleached in a solution containing chromic acid and potassium ferrocyanide, afterwards cleared in potassium metabisulphite, and then washed and dried. Hamburger claimed that the positive from film 1 (the orthochromatic film) exhibited a gradation from red to yellow, whereas the positive printed from film 2 (the panchromatic) had all tones from green to blue. The whole, therefore, giving the effect of a four-colour process! The bleached silver image furthermore provided a grey key. However, this effect was due probably far more to the fact that the clearing action of the metabisulphite is quicker for the pink than for the yellow, which resulted in the lighter tones tending to become yelloworange while the deeper tones remained red (Figs. 89 and 90).
With minor modifications the process was still being worked in London in 1933 exactly as above described. Negatives were generally taken by Agfa or Du Pont bipack instead of in the beam-splitter camera, a Debrie bipack camera being employed.
The most interesting contribution to the technique of dyemordanting processes made by Hamburger lay in the order of his procedure. He was probably the first to dye the film first and to bleach and mordant afterwards. This method seems to have resulted in a considerable gain in evenness, as mordanting processes are notoriously liable to yield continuously variable colour, than which there is no more disagreeable fault in colour films.
(Klein, Adrian Bernhard = Cornwell-Clyne (1940): Colour Cinematography. Boston: American Photographic Pub. Co.. 2nd revised edition, pp. 207-209.)
Two/four-colour subtractive process
Polychromide was developed initially as a process for still photography between 1911 and 1914 by the American Aaron Hamburger, who owned a photographic studio in Dover Street in London. Hamburger went on to become the editor for the Gaumont cinemagazine Around the Town when it began in 1919, by which time he was adapting his still colour process for moving images, first patenting and demonstrating his process for cinematography in 1922. Ostensibly this was a two-colour process, although four coloured dyes were used in the processing stage, giving a broader palette than standard two colour could offer. A beam splitter in the camera split the light from the object and recorded the red-yellow portion of the scene on one film and the blue-green on another. This was eventually replaced by the use of bipack film. The two negatives were then printed onto duplitised stock, one on each side in precise register simultaneously using a specially developed printer. The blue-green image was then dyed with a mixture of red and yellow, while the red-yellow image was dyed with a mixture of blue and green. One important innovation made by Hamburger was that the process was the first to fix dyes using a chemical mordant. This would become standard for the majority of subtractive processes, including Technicolor.
British Polychromide Ltd was formed to exploit the process, and Polychromide was adopted by British Pathé News in the 1920s for occasional use in its Pathé Pictorial and Eve’s Film Review cinemagazines alongside Pathécolor. It was briefly marketed by Pathé under the name Verachrome between 1923 and 1925. An interesting scientific coup came in 1927 when British Polychromide Ltd took a colour film of the total eclipse of the sun which took place on 29 June. The film was taken in Giggleswick in North Yorkshire and was shown on 11 November to the Royal Astronomical Society. In 1928 the delegates of the Seventh International Congress of Photography visited the Polychromide works where both still and moving images were printed.
Hamburger died in 1932, and his patents were taken over by a new company, British Colour Films Ltd, registered in 1933 to market the process. This was, however, unsuccessful and the processing plant was disbanded in 1937.
The BFI National Archive holds a compilation from 1926 entitled ‘Selections Illustrating the British Polychromide Colour Process’ which includes the 1927 film of the eclipse.
The film How I Play Tennis by Mile Suzanne Lenglen (1925) is available to view via the British Pathé News website at
The colour is not replicated online but the intertitles state that sections are in Veracolor.
‘Polychromide Colour Process: Photographic Congress Delegates Visit Hamburger’s Studio’, Kinematograph Weekly, 19 July 1928, p. 59.
Coe, Brian, The History of Movie Photography (London: Ash & Grant, 1981), p. 128.
Cornwell-Clyne, Adrian, Colour Cinematography (London: Chapman & Hall, 3rd edn, 1951), pp. 18, 339-41.
Ryan, Roderick T., A History of Motion Picture Colour Technology (New York: Focal Press, 1977), pp. 75-7.”
(Brown, Simon (2012): Technical Appendix. In: Sarah Street: Colour Films in Britain. The Negotiation of Innovation 1900-55. Basingstoke, Hampshire: Palgrave Macmillan, pp. 259-287, on p. 278.)
The first commercial use of silver toning for color prints was a system called Polychromide, involving a combination of carbon printing and toning of a silver image. It was invented by the American chemist Aron Hamburger, who secured a patent for it in 1913.8 The tricolor image was obtained by using a bromide paper toned yellow by converting the silver image into a complex of silver, iodine, chromium, and mercury that served as the base of the print. A magenta layer obtained from a pigment paper similar to that used in carbon printing was superimposed in register over the yellow print. Finally, the top, cyan, layer made on a stripping paper toned blue was transferred on top of the two other colors to form a full-color image (Fig. 8.3). It took about four hours to make a print, which was considered fast at that time (BJP 1914b). The printing technique was used exclusively at Dover Street Studio in London, where Hamburger was managing director; Polychromide prints were sometimes called Dovertypes.9 The studio exhibited numerous examples at the Annual Exhibition of the Royal Photographic Society in 1914 and produced Polychromide prints until the onset of World War I (Science & Society Picture Library 2011).
8 U.S. Patent 1,059,867 (1913).
9 Dover Street Studio was one of the leading commercial photographic companies specializing in theatrical portraiture. Based at 38 Dover Street, London, the company was the successor to Biograph Studios, whose negatives and stock they took over (National Portrait Gallery 2012).
British Journal of Photography (BJP). 1914b. “The Polychromide Colour Process.” British Journal of Photography Monthly Supplement on Colour Photography 8 (Dec. 4): 45–47.
National Portrait Gallery. 2012. The Dover Street Studios Ltd. www.npg.org.uk/collections/search/person/mp59318/the-dover-street-studios-ltd.
Science & Society Picture Library. 2011. http://www.scienceandsociety.co.uk/results.asp?image=io302223.”
(Pénichon, Sylvie (2013): Twentieth Century Colour Photographs. The Complete Guide to Processes, Identification & Preservation. London, Los Angeles: Thames & Hudson, on pp. 278–279.)
“I have to keep on reminding myself of these obvious facts when I see colour films. Each time I see a colour film I am impressed afresh with the visual strain of watching a colour subject, and I am tempted to say that colour films are “not wanted,” except for brief snatches. The answer is that we don’t find a strain in watching the colours in nature, and when our colour films approximate to the half-tints of nature, they will be pleasing and not a strain. A few of us went round to the Polychromide place this week and looked over the new process. At times the effect on the screen was like those crude semi-obscene postcards, seen chiefly at the seaside and at a certain kind of tobacconist’s. At other times, however, the results were astonishingly beautiful and harmonious. Even the best seemed to involve more effort to watch than a monochrome picture. I incline to the view that when colour comes, it will be most acceptable when it is in half-tones and subdued tints which surround us in life.”
(Anonymous (1928): Doubts on Colour. In: The Bioscope, 1151,LXXVII, Oct., p. 28.)
“An interesting demonstration was given yesterday by British Polychromide, Ltd., to a special representative of The Bioscope, of the processes by which their colour films are produced. A special camera is, of course, necessary, and this camera, using a single lens, takes two images simultaneously by means of a refracting prism. These negatives are used for printing on both sides of a double-sided positive stock. No difficulty is experienced in securing perfect registration and the image printed on one side is prevented from travelling through to the other by means of a special yellow dye, which disappears in the chemical process.
One side of the positive is then stained green and the other red by means of pad wheels. The film then passes into a special pigmenting bath, where the soluble dye is fixed in an insoluble form where the image has been developed. The remainder of the dye remains in soluble form and is washed off in a subsequent bath. The process takes very little longer than ordinary black-and-white films, and the price is much lower than anything of a similar type at present on the market.
For some time past sections of Pathé Pictorial and Eve’s Review have been done in this process, and a number of selections were projected for demonstration purposes. Though the colour effects at times are crude, and though the colours of dresses in the middle distance are apt to change in hue and luminosity as they approach the foreground, the process as a whole must be recognised as marking a definite advance in colour photography. Many of the effects produced are exceedingly beautiful, and give a very wide range of delicate colour gradations. The tendency to over colour the film is one that can doubtless be remedied in dyeing as public taste expresses itself. The whole process, while showing certain crudities almost inevitable at this stage, can claim to be a thoroughly practical method of faithfully reproducing a wide range of delicate shades and would seem to have profitable prospects. The polychromide process is also applicable to “still” photographs.”
(Anonymous (1928): Polychromide Process Demonstrated. Two Negatives and Double-Sided Positive. In: The Bioscope, 1151,LXXVII, Oct., p. 23.)
“As reported elsewhere in this issue, a demonstration of the above-named process was given at the Plaza, London, last Friday. Polychromide is described as a four-colour process. A special patented camera is used by means of which two negatives are taken simultaneously, the light, after passing the lens, being deflected to the films by a system of prisms.
One negative is sensitised to the colour gradations of yellow and red and the other to those of green to blue violet. The positive film is coated with emulsion on both sides and during printing is placed between the two negatives. Printing from both negatives is carried on simultaneously.
The positive film is developed in the ordinary way and is next coated on one side with a mixture of red and yellow dyes and on the other side with a mixture of green and blue violet dyes. The action of a pigmenting bath which affects the silver image chemically results in the hitherto black and white photographs becoming coloured pictures.
These colour films are said to take only an hour and a quarter longer than ordinary black and white pictures to produce, and it is claimed that they can be made at a lower price than any other colour film.
These films can be projected on any standard projector at any ordinary running speed, no attachment of any kind being necessary.
Screen results, as witnessed at the Plaza, were rather disappointing. The reds were too brown and the yellow appeared to be almost non-existent. It was stated that these defects were due to the blue violet colour of the arc used for projection, and that they could be overcome by the introduction of a piece of coloured glass between the arc and the film. But at the demonstration this simple expedient was not resorted to. However, the system is interesting and its further developments will be awaited with interest.”
(Anonymous (1928): The Polychromide Colour Process. In: The Bioscope, 1151,LXXVII, Oct., p. x.)