|Early Kodacolor & Ektacolor print material - researched by Michael Talbert|
Index to this web
For an insight into what is happening with Kodak since its fall, here
is a link to a New York Times Business Day article,
by Quentin Hardy dated March 20th, 2015.
Many illustrative images, provided
by Michael Talbert, are embedded within the following text.
16mm home ciné colour film, named Kodacolor, appeared in 1928. Improved colour in the form of Kodachrome then arrived in the 16mm ciné format in 1935 and by 1936 Kodachrome was also available in 8mm ciné and 35mm still formats. The early 1928 Kodacolor was a lenticular additive colour film which employed the 'lenticular' process which made use of a black and white film stock, the base of which was embossed with a large number of minute lenses or cylidrical ribs, 22 elements per millimetre. When exposed through the base using a camera lens fitted with a banded three-colour filter, the image was recorded as a number of colour separation elements which, after a reversal processing, could be projected through a similar lens and filter to produce the original colours. The process, which had a number of disadvantages, was discontinued in 1935 with the introduction of Kodachrome.
By the early 1930's, colour photography had reached well past the experimental stage. When Agfacolor Neu reversal film first made its appearance in 1936 it proved that a multi-layer colour film could be manufactured with the colour couplers incorporated into the three separate emulsion layers coated on the same support and processed in a single colour developer. A year previous to this, Eastman Kodak had marketed 16mm Kodachrome motion picture film but had chosen to process the film by a method of including the colour couplers for the three emulsion layers in three separate colour developers. Initially the processing procedure was extremely complicated. Not only were there three separate colour developers involved, but the film also had to be put through three separate Dye Bleach baths, each penetrating the emulsion layers to a varying extent.
The first step was a black
and white developer, which produced a black and white negative
image in each layer. As this was not wanted, it was removed by
a bleaching bath.
In 1938 the process was much simplified and the re-exposure step was made with red light fogging the bottom layer, which was then developed, then blue light for the top layer, which was then developed, and finally, the magenta layer was chemically fogged, and developed in the magenta developer. The selective exposures made sure that only one layer could be developed at a time. Although much simplified, the sequence was still too complicated to be carried out by a photographer using equipment in his own darkroom.
Colour prints at that time were being made from transparencies by manual 'registration' methods such as "Tri-Chrome Carbro" and the "Kodak Wash-Off Relief", plus others. Mainly, these printing processes were only used by professional advertising photographers, since they were difficult to manipulate and involved much time and skill to get the best result, making the cost of even one print well beyond the pocket of the average amateur photographer. However, by 1941, Eastman Kodak had introduced a fairly quick and relatively cheap method of making prints from Kodachrome transparencies. Despite this facility, a colour transparency is not the ideal starting point for making a good colour print. The brightness range of the average Kodachrome could not be accommodated satisfactorily on the printing paper, resulting in white, burnt out, highlights and black shadows lacking in detail.
In the late 1930s, Eastman Kodak were making experimental prints from Kodachrome transparencies onto a white plastic film base coated with a type of Kodachrome emulsion. This produced a reversal print from the Kodachrome slide.
In September 1941, Eastman
Kodak began two types of colour print services:
Eastman Kodak were also considering manufacturing a negative/positive version of Kodachrome.The negative and a print material would both have to be processed by the intricate method of the Kodachrome process. It was decided that the whole concept would have been far too complicated to put into practise.
Masks made from Kodachrome Sheet Film Transparencies for Kotavachrome
Each mask was made on Kodak Masking Panchromatic Film. Masking Panchromatic was a black and white sheet film which had a thin removable light sensitive layer attached to the film base. In total darkness, or under very dim dark green safelighting, this layer was carefully removed from its base and cemented onto the emulsion side of the Kodachrome sheet film transparency to be printed. The base side of the masking films removable layer was in contact with the emulsion side of the transparency.
The Kodachrome was then exposed through the base, the emulsion side facing away from the light source, thus printing the highlights onto the layer of the masking film. Most masks were exposed with a red filter in front of the light source which improved the colour rendering of the greens and cyans in the Kotavachrome print.
The exposed mask was processed to a negative while still attached to the transparency, the layer of film protecting the emulsion side of the Kodachrome from any harmful black and white processing chemicals. The mask layer was attached to the Kodachrome with its emulsion side outwards, so as to allow the black and white developing chemicals to act on the b&w layer.
When processed and dried, the combination was used to expose the Kotavachrome print material, again exposing with the base of the Kodachrome facing the light source. After the print was processed, the mask layer of film was peeled off the transparency. Unlike other methods of masking, which required a separate piece of film to be registered with the transparency, there were no registration problems using this method as the mask, once exposed, never left the transparency until after the final print was made.
(For a more complete explanation on masking using a separate film and for colour correction see Duplicating Transparencies)
Although Minicolor prints were made from amateur photographers 35 mm transparencies, Eastman Kodak also made Kotavachrome prints from 35mm Kodachromes. The 35mm size was masked in the same way but the protective layer of varnish on 35 mm films had to be removed before the masking layer could be attached.
Kodak Masking Panchromatic
Film was available in various sizes, viz:
Although Kotavachrome prints could only be made by Eastman Kodak, the Masking Panchromatic film was also used by Colour Laboratories and Professional Photographers making colour prints from transparencies by the Kodak Wash Off Relief Process, which became known as the Dye Transfer process after 1945 in the U.S.A.
In 1939, Vittum and Jelly, of Eastman Kodak, discovered a type of colour coupler which, unlike the Kodachrome developer couplers, could be combined with the three emulsion layers of a colour film. The new couplers were incorporated into a resinous binder. They were known as Protected Couplers, as they were carried in small particles of organic materials which protected them from any reactions of the silver bromide emulsions. The colour couplers were then within the emulsion but not in complete physical contact with it.
Like Agfas Agfacolor Neu film of 1936, any colour material, film or paper, having the colour couplers combined with the three emulsion layers at the time of manufacture, could be processed in a much simpler, and much faster, manner than that of Kodachrome. Only one colour developer and one bleach bath were required.
The first film manufactured by Eastman Kodak containing Protected Couplers was Kodacolor Aero Reversible Film in 1940. Mainly used by the United States Army Air Force for reconnaissance purposes, the special feature of this film was that it could be processed anywhere without elaborate equipment. Kits of chemicals for making up the five processing baths were available. Processing was much like E1 but with longer times, very likely processing at 68°F (20°C). The time taken to process the film, not including drying, was around 90 minutes.
Despite the name Kodacolor, the film produced a transparency after processing, and bore no relationship, apart from the colour couplers, to the eventual Kodacolor negative film.The processing sequence and chemical baths for Kodacolor Aero Reversible film were not unlike the processing procedure and baths for the earliest type of Kodak Ektachrome sheet films (see here).
It was probably about 6 to 10 ASA and had a high contrast.
Two sets of filters were supplied with the film, one filter to correct for the various emulsion differences, and to balance it for average daylight. The other filter, or filters, were to correct for haze, or blueishness in distant subjects. The Haze filters were likely to have been, Wratten Filter No.1, and Wratten Filter No.2A, 2A being slightly stronger.
It was replaced, or renamed, Ektachrome Aero film High contrast, possibly in 1946.
In the U.S.A., before World War II, there was a definite desire amongst amateur photographers for a film which produced prints in colour, just as easily as black and white negative film. The photographer could then order one print for his album, one for his friends, and one to put in a frame.
In November 1941, the Director of Research at the Eastman Kodak Company, Dr. Kenneth Mees, outlined an entirely new system for making colour prints from a colour negative film - called Kodacolor. The announcement was entitled "Direct Processes for Making Photographic Prints in Color, communication No.832, from Kodak Research Laboratories. Like Kodachrome, this film was coated with three light sensitive layers, sensitive to red, green, and blue light. Each layer incorporated colour couplers, like Kodacolor Aero film, and after exposure the film could be developed in a single colour developer, producing a colour image in each layer. After bleaching and fixing, an image of pure dyes was formed of the original subject.
However, this was where the similarity between previous colour films ended. Unlike Kodachrome, or Kodacolor Aero film, this was a negative image, colours were reversed as well as density. Areas of blue sky reproduced as dark yellow, grass became pink, and reds became blue-green. The photographic colour printing terms of "pink" and "blue-green" are the subtractive colours magenta and cyan.
All processing of Kodacolor films was undertaken by Eastman Kodak at Rochester N.Y. The photographer handed in his exposed films to a Kodak dealer who sent the films to Eastman Kodak at Rochester. The cost of processing the film was included in the film price at the time of purchase but did not include the cost of any prints.
To allow the film to be used in fairly basic, non adjustable cameras, the film speed of Kodacolor was at least twice that of Kodachrome. A Weston rating of 20 (25 ASA or ISO) was quoted in the data sheets. This was adequate for an exposure of 1/50th of a second at f11 for an average subject in bright sunlight. Initially, the film was balanced for daylight and blue flashbulb exposures. The data sheets gave specific instructions for "fill-in" flash exposures using Nos. 21B and 5B photoflash lamps. The film speed was increased by one third of an f-stop in 1955, to Weston 25, or 32ASA/ISO.
Although the Kodak Data book - "Kodachrome and Kodacolor Films" mentions that Kodacolor film had a limited exposure latitude compared with black and white films, it also pointed out "Satisfactory Kodacolor prints can be made from Kodacolor negatives which received as much as two full f-stops more than the correct exposure". However, overexposed negatives generally gave a lack of detail in the highlights of the print, while under exposure caused black shadows and low contrast prints. Photographers were also warned that Kodacolor pictures made on dull, overcast, cloudy days tended to turn out flat (lacking in contrast) and with a blueish colour cast.
Good black and white prints could be made from Kodacolor negatives, and so a colour negative which had been incorrectly exposed, or lacked colour accuracy due to being exposed under mixed lighting conditions, could often be used to at least produce a satisfactory black and white print.
Eastman Kodak described "Kodacolor" as a "colour medium for snapshotters", who prefered a colour print as their end result, as opposed to a Kodachrome transparency. Kodacolor gave pleasing, attractive colour prints but the process could not give exact colour fidelity. Reds and blues were reproduced well, yellows were rather dull, while greens tended to be tinged with blue.
The structure of the film was similar to the early Agfacolor negative film, consisting of three colour sensitive layers. The Red sensitive layer, producing the cyan dye image, was coated on the base of the film. On top of the red sensitive layer was coated the green sensitive, producing a magenta dye image, then a yellow filter layer, and on top, a blue sensitive layer, giving a yellow dye image.
The film was principally intended for amateur photographers, with simple, basic roll film cameras. In 1942, when Kodacolor first appeared (in the US) roll films were available in six different sizes:- 127, 120, 620, 116, 616, and 122. 35mm Kodacolor film was not manufactured because this film size was well catered for by Kodachrome and, at that time, the enlarging of a small 35mm image would have shown the granular structure of the early Kodacolor film in print areas of medium density, such as a cloudless sky.
At that time, all processing and printing of Kodacolor film was carried out by Eastman Kodak at their laboratories at Rochester, N.Y. The photographer handed in his exposed rolls of film to a Kodak photographic dealer who then sent the films to Rochester for either, developing only or develop and print. The purchase price of the film included developing only. In the first instance the photographer was able to see the negatives before ordering prints. Then he selected the best exposed negatives and marked the order e.g.one off or two off as the case might be.
In Develop and Print there was no way the photographer could see the negatives before they were printed, and he had to take a chance on whether his exposures were correct. Eastman Kodak printed one print off each of the negatives according to the negative quality within certain limits. Some negatives may have been judged by the printer as too bad to print (gross underexposure, fogged), and if these particular negatives were important to the photographer for personal reasons, those negatives had to be returned by the owner marked Print regardless.
All prints, irrespective of negative size, were made 2&7/8ins wide plus white borders of about ¼ins all round. The length depended upon the length of the negative. The smallest prints were from square negative, and the largest from size 122 rollfilm, which, in some cameras, produced a massive 3¼ x 5½ ins negative. The print size from these negatives was 2&7/8ins x 5&1/8ins, a little smaller than the negative! However, 122 rollfilm was short lived, by 1948 this size was no longer manufactured in Kodacolor.
Fronm 1942 to 1955 three kinds of Kodacolor were manufactured by Eastman-Kodak, each an improved version of the proceeding one. The first two versions were balanced for daylight.
Film in 1942
Film in 1944
To alleviate this problem, from 1944 an extra emulsion layer was included, between the yellow filter layer and the green sensitive, magenta dye forming layer. This layer acted as a positive mask. Its function was to decrease the contrast of the colour negative as a whole but without any loss of colour saturation.
The actual layer itself was a black and white emulsion, sensitive only to blue light. It was too slow to be affected by the camera exposure, its speed being much the same as a Process film or Line film emulsion. Process film was a slow speed, high contrast, blue sensitive film, used for copying black and white line originals, and for making positive transparencies from soft black and white negatives. It was faster and less contrasty than Line Film. Line film was a very slow speed, very high contrast blue sensitive film for making line negatives from architects and engineers plans and drawings. Both films had various uses in photolithography.
As a result of the positive mask layer, the colour negatives appeared rather heavy regardless of exposure and required a longer printing exposure. It is believed that processing of the film took slightly longer because the mask layer had to be developed separately to the three colour sensitive layers.
After processing the mask held back some of the light projected through the shadow areas of the negative. Since the mask added density to the shadow areas, less light could reach the printing paper from the shadow area, so the printing exposure could be increased to put more detail into the highlights of the print, thus lowering the overall contrast. The mask only added density to the shadow areas of the negative.
Kodacolor film with the black and white mask was marketed from 1944 to 1949.
Film in 1949
~ Colour masked Kodacolor Film.
Due to the dye deficiencies, the magenta dye absorbed some blue light, which it should have passed freely, and the cyan dye absorbed a portion of light of its own colour. Prints made from Kodacolor negatives showed greens tending towards blue and weak reds. In the first case the blue light which was being absorbed by the magenta dye should have been used to make the green yellower. In the second case the portion of cyan dye that was being absorbed by its own layer should have been used to make the print redder. More blue light makes the print yellower, and more cyan light makes the print redder. If the green in the print was too blue and a blue filter was inserted in the printer to correct this, it is likely the whole print would turn out too yellow, as the other colours in the print would have been correct, or nearly so.
A solution to this problem of dye deficiencies was first thought of by W.T.Hanson of Eastman Kodak in 1943. His proposal was to create a mask in the film by making use of coloured couplers to correct for the overlapping absorptions of the cyan and magenta dyes.
The coloured mask was actually a positive image, exactly registered with a defective negative dye image. The coloured mask corrected the dye deficiencies in the negative image to the extent of the overlapping absorptions. The negatives took on an orangered colour.
Kodacolor film with integral coloured masking as it was called, was produced from 1949, and in the same year an artificial light version of the film was launched (see left). It was balanced for Type A photoflood lamps (approximately 3400°K). Its speed to photoflood lighting was 20ASA and it could be exposed to daylight with a Kodachrome Type A filter, No. 85 at 12ASA.
|Kodacolor Film in 1955 ~ Process C-22||
Kodacolor Universal film replaced both Daylight and Type A Kodacolor in 1955. The Universal film was balanced for Clear flashbulbs and was one third of a stop faster at 32ASA.
Alongside is ahown the cover of a Kodacolor Booklet of 32 pages, published by Eastman Kodak Company, publication No. E 10, in March 1955.
Intended primarily for the amateur photographer, it contains information on Outdoor Pictures, Flash Pictures, Exposure Tables, Flood Lamp Pictures and Ordering Prints and Enlargements.
There are several exposure tables, for Daylight and Type A films.
Illustrated with some very well reproduced square colour pictures, as the film was only available in roll film sizes in 1955.
Inside the front cover there is stuck an information sheet advising of changes to Kodacolor film. It states that a new film, Kodacolor Universal Type, is now available, replacing the Daylight type, and the Type A films. The sheet gives new flash distances for some Kodak cameras and a table of new Flash Guide Numbers.
Kodacolor Universal Type film was sold at a price that did not include the cost of developing to a negative, unlike the previous Kodacolor films.
Kodacolor Roll Film comes to the UK, October
not widely available to the general public until Spring 1958
The trouble with unwanted absorption by these cyan, magenta and yellow dyes has been overcome to a large extent by Kodak in Ektacolor and Kodacolor (the former being a professional film) and in the cine film known as Eastmancolor, by using an integral masking system. A similar system has been adopted by Imperial Chemical Industries in the new ICIcolor. The colour-forming chemicals incorporated in colour negative processes are themselves normally colourless before development and only become coloured during processing, when the particular dye, be it cyan, magenta or yellow, is produced in the particular layer in proportion to the blackening of the silver. That is to say, if in the negative light has not acted at all on the emulsion there will be no blackening of silver and no conversion of the colour-forming material into the particular dye. On the other hand, if the emulsion has been fully exposed to light the maximum amount of dye is produced together with the maximum blackening of the silver. In the subsequent bleaching process the blackened silver is removed leaving only the dye image. Now if we consider the cyan layer as fully exposed to light, then after the bleaching and fixing we get a layer of cyan dye, the function of which is to absorb red. Now, as we have indicated above, this cyan dye also absorbs some blue, thereby usurping to some extent the function of the yellow layer. Let us imagine this cyan layer had 20 per cent unwanted absorption of blue. The method adopted in integral masking is to make this colour-forming material yellow in its normal state instead of colourless. Then, if no light action has occurred in the emulsion, after bleaching and fixing we shall have a plain yellow dye absorbing say 20 per cent of the blue. If on the other hand the silver has been fully affected by exposure and fully blackened, then after bleaching and fixing we shall have a cyan dye also absorbing 20 per cent of the blue. In other words, no matter what amount of blackening or what variations of exposure are given to the particular layer, it will have a uniform absorption of 20 per cent of the blue, irrespective of gradation. We are not giving actual figures but merely giving a theoretical example.
In a similar way the magenta layer, whose function is to absorb green, but which may absorb say 15 per cent of the blue, is also made coloured, the particular yellow or orange coloration being so arranged as to absorb the same percentage of blue as the magenta does when fully developed. The yellow layer, which produces very efficient dye, is not treated in any way, but the two colourings in the magenta and the cyan layer can be made to compensate to a very large extent for the faults in these dyes. An integrally masked negative, such as Ektacolor, Kodacolor, ICIcolour or Eastmancolor when held up to the light appears strongly orange owing to this additional blue and green absorption, but when placed in the enlarger and projection printed on to similar tripack paper (which does not contain any masking dyes) the final result is very similar to that which will be produced with a theoretically perfect cyan and magenta dye. The fact that the negative looks a very peculiar deep orange is very puzzling to the uninitiated, but it must be remembered that the appearance of the negative is not important so long as the final result is what we require.
Our own tests, using the British-made
material, showed that the prints now being produced are very
good indeed. Their prices are as follows:
In July 1958, MCM reported
in its "New York Letter":
Process C-22 KODACOLOR Films
To view a picture of box of 120 Kodacolor roll film (as manufactured around 1959) and Kodacolor X roll film (as manufactured around 1966), click here.
Kodacolor X remained on the
market until 1975, but thereafter the C-22 Kodacolor & Kodacolor
X films were gone forever. However, the C-22 process lived on
for another four years.
The C-22 process was last mentioned in the British Journal of Photography Annual (BJPA) 1985 edition, with formulae and processing steps.
C-41 KODACOLOR II Films
Internegative Films were used
for making negatives from transparencies, the negatives then
being printed onto Ektacolor paper.
Although more direct methods of making colour prints directly from colour transparencies have been used since 1941, a colour internegative generally gave a far better reproduction of a transparency compared to a print made using colour reversal paper (see Kotavachrome prints and Kodak Colour Print Material, Type R)
Earliest 'Colour Internegative' films for still photography
Eastman Kodak introduced Eastmancolor Internegative Film Type 5243 in 1951 for use in the Motion Picture industry. It is possible that internegatives were made on this film from release prints made on Eastmancolor Print Film, Type 5381 .
In the USA, Eastman Kodak began a service in 1949 for making colour prints from amateurs colour transparencies. The transparencies, mainly 35mm, were printed onto Kodacolor (camera type) film, possibly Type A, and then prints were made from the internegatives on Kodacolor paper.
It is possible that the first type of internegative film specifically designed for making negatives directly from colour transparencies was Agfacolor ZN film. Agfacolor ZN film was an unmasked colour negative film, presumably balanced for tungsten illumination, which could be used to make contact or enlarged negatives from Agfacolor transparencies. Although the transparencies could be printed onto the film directly, Agfa recommended for best results a black and white contrast reducing mask should be made from the transparency first to be used in register with the transparency when printing onto the ZN film.
As far as is known, the film was introduced in 1956, and the development time in Agfacolor negative film developer S was 6 to 7 minutes. It is believed to have been taken off the market by the early 1970s.
On a personal note, Michael Talbert met someone who, allegedly, knew something about this film. Forty one years ago, while working as a colour printer in London and during a discussion with other printers, Agfacolor ZN film was mentioned. One of the printers was a German lady who ventured to say she had used, or at least known, something about the film. When asked if it was any good, she replied Rubbish !.
Ektacolor Internegative Film
The recommended procedure was to make a contrast reducing mask from the transparency onto Kodak Pan Masking film. This was registered and attached to the transparency when enlarging and exposing the transparency onto Ektacolor Type B or Type L film. The mask then reduced the contrast to the level that could be accommodated on the Ektacolor films.
Printing the transparency directly onto Ektacolor film did not work as the internegative would be far too contrasty and the print would exhibit burnt out highlights and dense shadows with no detail in them. The author has tried this method of making internegatives on Ektacolor Professional Type L film and came to the conclusion that only an extremely soft contrast transparency would give an acceptable result.
Prints made from internegatives made on Ektacolor Type B and L films, in which the colour laboratory had taken the trouble to make the internegative from a masked transparency, gave good results, but the masking was a separate and time consuming procedure and added to the cost of the internegative.
In 1961, Eastman Kodak introduced Ektacolor Internegative Film in sheets, and Internegative Color Film in 35mm rolls. Transparencies could be printed onto these film without the need for masking.
Ektacolor Internegative Film is mentioned in the Kodak Data book, Color Films, 4th edition, published in December 1961. The book mentions that Information on producing internegatives on this film could be obtained by request from the Sales Division at Eastman Kodak, Rochester 4 N.Y.
In the UK, in the Kodak Professional Catalogue for 1963 the 35mm version of internegative film is listed for sale in lengths of 80 feet.
Ektacolor Internegative sheet film was first listed in the Kodak Professional Catalogue for 1964 to 65 for the UK, where three sizes are offered for sale 4 x 5 inches, 5 x 7 inches and 8 x 10 inches.
Ektacolor Internegative film in sheet film format was designed to make internegatives at exposure times of 1 to 16 seconds with a 3200°K light source.
Most internegatives were made through an enlarger with a colour head, enlarging 2¼ inch square transparencies onto 4 x 5 inch sheet film to make an internegative about 3¾ inches square from the whole of the transparency. 35mm transparencies were enlarged to about 4¾ x 3 inches and negatives from 5 x 4 inch transparencies were made to 3½ x 4½ inches. The larger the print ordered from the transparency the larger the internegative. 10 x 8 inch negatives were not uncommon when making mural sized prints.
the exposure and 'shadow to highlight' balance for batches of
The suggested starting exposure was 10 seconds and, with the filtration of 50 20 --, three or four trial internegatives were exposed at different apertures, keeping the exposure at 10 seconds. When processed and dried, one of these tests would have been correctly exposed, or very nearly so.
A correctly exposed internegative tends to look slightly thinner than a correctly exposed camera film negative, such as a negative made on Vericolor or Ektacolor films.
The best possible print was then made from the chosen test internegative, concentrating on filtering the mid tones to the correct balance
If the mid tones had been filtered as near as possible to a fairly neutral balance, it is likely that the high lights would show a colour cast, and the blacks and shadow areas would show the opposite cast.
For example, if the colour cast in the high lights was Magenta, the shadow areas tended to look green. This meant that the contrast of the green sensitive layer was too low.
In this case, it was possible to correct the balance of the print by adding a filter of the same colour cast as the overall shadow area cast or, better still, decreasing the filtration of the opposite colour, magenta.
The starting filtration was 50 Yellow, 20 Magenta, so another test internegative was exposed at, say, 50 Yellow, 10 Magenta, and another test at 50 Yellow, 5 Magenta, keeping the exposure time slightly less this time, on account of the change in filtration, i.e. say to 9 seconds and 8 seconds, respectively.
The contrast of the internegatives could also be corrected at this point. If the test print was too low in contrast, a slight increase in exposure would increase contrast. If too high in contrast, a slight decrease in exposure would lower the contrast. Suppose in this case the contrast was judged to be too low. The test internegatives could be exposed at 14 seconds and 12 seconds, respectively.
One of the prints made from the second test internegatives would have shown an improved colour balance in the print. The internegative exposure giving the best print could be used for making internegatives from the vast majority of transparencies. The exposure of the internegative film could be increased or decreased according to the contrast of the transparency. With experience, the shadow to highlight balance of badly exposed transparencies with colour casts could be modified by filtration and exposure changes to give a much improved copy.
Very under-exposed transparencies were given one stop more exposure by altering the aperture of the enlarger lens and, correspondingly, very over-exposed transparencies were given one stop less exposure. Similar to duplicating, under exposed transparencies always printed more successfully.
During the early 1970s, the exposure range was changed to 1/10 second to 16 seconds.
Described above is a method of finding the correct filtration and exposure for any batch of internegative film by trial and error. The Kodak instruction leaflet enclosed in every box of film gave an alternative procedure. This involved taking densitometric readings from grey scales exposed onto internegative film with a densitometer and plotting three separate D log E curves* of the red, green and blue densities of each film layer.
(*D log E = density of the actual dye in the film plotted against the logarithm of the exposure)
Both methods work, but the one described in the text, above, is possibly easier to carry out, achieves the same result in the end, and doesn't require any knowledge of photographic densitometers (and equipment) or of plotting graphs.
Listed in the Kodak Professional Catalogue for the UK in 1963 as Kodak Internegative Color Film, the description mentions that the film could be processed in C-22 chemicals with a modification to the development time. This was very likely to be a reduction in the time of the development, normally 12 minutes as for Kodacolor or Kodacolor X film in 1964.
By the late 1960s the film became known as Kodak Internegative Color Film 6008 and by then it was recommended that development was carried out in the special Internegative developer consisting of Internegative Replenisher and Internegative Starting solution. Development time was 6 minutes and the remaining solutions were the normal C-22 chemicals and timings.
In 1971 the film became Kodak Ektacolor Internegative Film 6008 to be replaced by Vericolor Internegative Film 6011 in 1978 (see below). This film was initially known as SO-406.
To view a picture showing boxes of Ektacolor Internegative Film and Ektacolor Print Film, click here.
Processing Kodak Ektacolor Internegative Film
It was not possible to process Ektacolor Internegative film by increasing the development time per number of sheets of film developed; only a Replenished process would give reliable results.
The developer working solution was made up of:
This was the actual solution in which the film was processed. The Replenisher solution on its own was used to replenish the working developer.
The development times for Ektacolor
Internegative films were 5 minutes for the sheet film or 6 minutes
for the 35mm film, and other sizes such as 46mm and 70mm.
The normal C-22 chemicals were used for the remainder of the process with exactly the same times and temperatures as camera sheet film.
The sheet film was generally
processed in 3½ US gallon tanks, or 3 gallon
tanks in the UK, with an increased agitation rate compared with
the camera sheet films.
The earliest 35mm version Kodak Internegative Colour Film, as listed in the Kodak Professional Catalogue in the UK for 1963, was processed in the C-22 developer for camera films with a reduction in development time.
When Michael Talbert made his first Internegatives using Ektacolor Internegative 5 inch x 4 inch sheet film, he processed them in the same C-22 developer as for camera films, but used 7 minutes at 75 +/ ½°F. It is possible that the earliest (pre-1964) version of Ektacolor Internegative in sheet form was intended to be developed in the C-22 camera film developer, with a reduction in the development time, as Michael has been unable to find any reference to the special Internegative Replenisher or Starting Solution before 1964.
Kodak Ektacolor Internegative Film 6110, and Ektacolor Internegative Film 6008, were replaced by the Vericolor Internegative fims, 4112 in sheet sizes, and 6011 in 35mm size, at the end of 1978. In 1979, Vericolor Internegative Film 4112 was available in the UK in 4 x 5 inches, 5 x 7 inches and 8 x 10 inches. Type 6011 was available in 35mm x 80 foot rolls.
Vericolor Internegative films were originally designed for an exposure range of 1/1000 second to 30 seconds with tungsten 3200°K lamps, but during the 1980s the exposure range was changed to 1/10 second to 30 seconds.
The film could be balanced for exposure and filtration by following the same procedure as for Ektacolor Internegative films (see above). A starting filtration of 30 Yellow, 10 Magenta i.e (30 10 --), was recommended by Kodak,using a trial exposure of about 10 seconds. The Kodak Data sheet E-24 (H) described a technique of balancing Vericolor Internegative films.
They were developed in the normal C-41 process with development times and replenishment rates as for Vericolor II camera films. No special developer was needed. The Vericolor Internegative and Print Films were only intended for laboratory use & processing, not for exposure in a camera.
Vericolor Internegative Film
The balancing procedure for the Kodak Vericolor Internegative films, 6011 and 4112, was described in the Kodak Data sheet E-24(H).
A densitometer was used to read the lowest and highest densities from a Kodak Three point transparency guide exposed on to the internegative film at a trial filtration of 30 Yellow, 10 Magenta with an exposure time of about 10 seconds. A Three point transparency guide was a transparent piece of film with three coloured patches, or areas, and three grey density patches, two of which were used to take the red, green and blue density readings.
The low density value readings corresponding to the red, green, and blue densities of the film dyes were subtracted from the red, green, and blue high density value readings to give Density Difference values. These three "density difference" values were compared to a table in the data sheet of Density Difference Aims. From the information in the data sheet the correct filtration for any batch of internegative film could be calculated by altering the trial filtration until the Density Difference values of the trial film were within the Density Difference Aims.
If the red, green, and blue values from a second trial exposure did not come within the "Density Difference Aims", it was suggested that an internegative was made from a correctly exposed well balanced transparency preferably with a substantial area of grey for colour matching, using the new filtration. The best possible print was made from the processed internegative.
The Kodak data sheet included a Guide for Adjusting Filter Pack for working out the correct filtration when judging colour casts in the high-light area of the print. Example: If the high-lights were Yellow, the Guide suggested removing 10 Yellow (if a slight cast), or 20 Yellow (if a noticeable cast), from the filtration.
The opposite of this would be to add 10 or 20 Blue, but almost all filtrations were in Yellow and Magenta when using Vericolor Internegative films.
Another trial internegative was made with the filtration change, and any contrast correction could be made at the same time. Contrast corrections were made exactly as on Ektacolor Internegative film (see above). As long as the final exposure was within the exposure limits of the film, the resulting exposure time and filtration could be used for making internegatives from most transparencies. A good final exposure time to aim for was from 8 to 12 seconds.
Internegative Film, 4114 Type 2
Vericolor Internegative film 4114 Type 2 was not intended as a replacement for Internegative 4112. Kodak Commercial Internegative Film 4325 replaced Internegative 4114 in 1993 but Internegative 4112 continued to be sold.
Vericolor Internegative 4114 Type 2 film was only recommended for making internegatives from transparencies, whereas Ektacolor Internegative film and Vericolor Internegative film 4112 could also be used to copy coloured art works, paintings, or any coloured flat copy. The contrast was changed in the same way as in making internegatives from transparencies.
4114 Type 2 sheet film was obtainable in the sizes: 4 x 5 inches; 5 x 7 inches; 8 x 10 inches.
Both Vericolor Internegative films were coated onto a Polyester tear-resistant base, the trade name was Estar Thick Base.
Kodak Data sheet E24(T) gives a Density Difference procedure for balancing this Type 2 film similar to the method given above for Vericolor Internegative film 4112,
A densitometer had to be used, but readings were taken from Kodak Photographic Step tablets, (Grey Scales, printed onto a strip of film), and the filtration changes could be read from a table in the data sheet showing plus or minus values to alter the Yellow, Magenta and Cyan filtration values.
The instructions packed in
each box of film gave a trial filtration for that particular
If the instructions for the film were mislaid, a filtration of 30 Magenta, 30 Yellow provided a good starting point.
Both films were designed for making internegatives from Kodachrome and Ektachrome original transparencies, or for photographing coloured originals on an opaque base, or for copying photographic colour prints. Kodak Vericolor Internegative film, 4112 (see above), was recommended for copying maps and flat artwork.The balancing procedure for both films was described in the Kodak technical data sheets E-225T. Four methods were given for finding the correct filtration and exposure.
The film was intended for use with a 3200°K light source (enlargers with colour heads), at exposure times of 1/10 second to 30 seconds. A first trial exposure would have been about 10 seconds using the suggested filtration printed on the label of the Internegative film box. The Data sheets also gave a starting filtration of 30 Magenta, 30 Yellow.
For photographers using the film for the first time, the Data sheets gave details of working out a Starting Exposure when using an enlarger to make internegatives. An exposure time of 10 seconds was suggested for the sheet film 4325 when the illumination at base board level without any filtration dialed in the colour head was 32 Lux, or 3 Foot Candles. An exposure for the 35mm film was 1 second with 323 Lux, or 30 Foot Candles.
A separate exposure meter could also be used to determine a starting exposure, or the exposure meter in a single lens reflex camera when using the 35 mm film. If the meter was set to 400 ISO (ASA), the correct exposure would be 1/8 second at F5.6. This exposure would apply to the sheet film and the 35mm film.
Both types of film were processed in C-41 chemicals, using the same timings and procedure as the camera films.
Commercial Internegative Film
4325 was obtainable in sheet format as:
Commercial Internegative Film 5325 was obtainable in 80 foot lengths in 35mm format.
These were the last Internegative films made by Kodak. As far as is known the manufacture of both formats ceased in 2006.
The images below were sent to Michael Talbert by Russ Chapman, living in Melbourne, Australia.
They are Kodak Internegative 5235 cross-sections. The measurements on each image (44.9microns left and 46.2microns right) are the swollen section dimensions (swollen in water) and would be about 200% more than an unswollen section. They were produced in 2005, shortly before the film was discontinued.
Russ says "Note the unusual emulsion arrangement. The additional magenta layer between TWO cyan emulsions (see processed image, RHS below). This was to provide additional interimage effects to enhance the colour reproduction characteristics of what was a quite complex emulsion of the time."
Vericolor Print Film
Vericolor Slide Film
There is little known of the methods and processing procedures Eastman Kodak used at Rochester to process the earliest versions of Kodacolor film. As early Kodacolor film was available only in roll film sizes, it is likely that dip and dunk film processing machines were used to develop the films to colour negatives. Modified black and white film processing machines may have been employed, more tanks being added for extra chemical solutions and washes.
to 1944 ~ Kodacolor Processing procedure
The temperature of the baths
is likely to have been around 68°F.
to 1949 ~ Kodacolor Processing (the second type of Kodacolor film)
The film had a black and white contrast mask layer between the yellow filter later and the green sensitive layer. The mask layer was a very slow speed, blue sensitive emulsion, too slow to be affected by any camera exposure. The film was processed to form a dye negative image in each of the three colour coupling layers. The film was then exposed to blue light through the base, printing the already developed cyan dye and magenta dye layers onto the mask layer. The exposure did not affect the blue sensitive top layer because the yellow filter , underneath the blue sensitive layer would stop any blue light. The mask layer was then processed in a soft working black and white developer to form a weak positive mask image of the shadow areas of the green sensitive layer and red sensitive layer. The exposure of this layer took place after the film had passed through the Bleach bath. The idea was, when the negative was printed onto Kodacolor paper, obviously through the base of he film,the mask would have held back some of the exposing light from the shadow areas of the negative, thus lowering the contrast.
The processing sequence may have been something like the one used for the original Kodacolor film outlined above but with additional steps.
Possible Processing Sequence:
Film Processing, 1949 1955 ~ (the third type of Kodacolor Film)
C-22 KODACOLOR Film Processing; post-1955 ~ (Universal type of Kodacolor
Film - see above)
The above C-22 process, dating from 195556, shows two processing times:
In 1963, Ektacolor Professional Type S roll film was introduced, the same emulsion as the sheet film on a roll film base. At first available in 120 and 620 rolls, it was joined by a 35mm size in 36 exposure cassettes and long lengths of bulk film a few years later.
About this time, the development time for all C-22 Kodacolor films was increased to 14 minutes, and the agitation rate was decreased to an initial 15 second agitation for the first minute and thereafter once per minute. It was then possible to process Kodacolor, Kodacolor X and Ektacolor Professional Type S roll and 35mm films in the same processing run. The time for the various sheet films remained the same as previous i.e. 14 minutes. By 1965, Kodacolor film was almost obsolete, having been replaced by the then new faster Kodacolor X.
The more modern, but high temperature (100°F), C-41 chemistry (see below) is incompatible with C-22 films, where the highest process temperature was 75°F. The higher C-41 temperature would damage the C-22 film emulsion. It might even strip it off its celluloid backing !
But it might be possisble to use a modified C-41 procedure. The C-41 Bleach and Fixer will work at 75°F as this was the lowest temperature for processing C-41 films; 6½ minutes in each. You could get away without using the Stabilizer. The Wash times might have to be increased by 50%.
The C-41 Development time is 3¼ minutes at 100°F. Working on the old black and white developer rule, where development time has to be doubled for each 10 degrees Fahrenheit reduction in temperature, would suggest 6½ minutes at 90°F, 13 minutes at 80°F, so about 19 minutes at 75°F.
Hence, it might be possible to colour develop a C-22 film in C-41 chemistry, all at 75°F.
try Black & White Processing Chemistry
The above site's owner puts colour films through Kodak HC 110 developer which is a bit like a liquid D-76, though maybe a bit more energetic than D-76. This route is almost certainly better than trying to develop out-dated colour negative film in hopes of achieving colour results, especially if the original colour chemistry is no longer available.
A new colour negative film, mainly intended for amateur photographers, was introduced in 1972. Compared with Kodacolor X film, KODACOLOR II film showed higher sharpness together with a micro-fine grain structure. At the time of its introduction, it was not a replacement film for Kodacolor X.
The film was initially intended to fit the new amateur Kodak Pocket Instamatic cameras taking 110 size film, a new format giving a negative size of only 13mmx17mm. The grain structure of the existing Kodacolor X and Ektacolor Professional colour negative films were not fine enough for use in the new ultra small 110 cameras. Following the idea of the original (1962) Instamatic cartridge Type 126 film, 110 films were sold in cartridges for slotting into the Kodak Pocket Instamatic cameras. The ultra small negatives were sharp enough to make enlargements up to 3½x4½inches. Prints much larger than this size showed objectional graininess.
The film was coded as:-
Kodacolor II could be given the same exposure times as Kodacolor X film. The daylight speed was 80 ASA (ISO), exposed without a filter. Photoflood speed was 25 ASA (ISO) with a Kodak No.80B filter. Tungsten speed (3200) was 20 ASA (ISO) with a Kodak 80A filter.
The negatives were suitable for printing onto Kodak Ektacolor 37RC paper.
Kodacolor II film was designed for processing in the new FLEXICOLOR chemistry, also known as Process C-41. Flexicolor chemicals were principally intended for machine processors. Kodacolor II film could not be processed in the recently marketed Vericolor chemicals, and Kodacolor II film was not an amateur version of the two Vericolor films.
Hence, in 1972, there were three Kodak colour negative processes:-
The films and the processes could not be interchanged (but see above for advice re: processing a C-22 film in C-41 chemistry).
C 41 using Flexicolor chemistry
and Tank continuous processors using C-41
Replenishment was generally automatic and the dwell time in each processing tank could be altered to suit each process, (C-22, E-3, E-4, C-41, Agfa Negative, and others including black and white films.). In the trade this type of processor was known as Dip and Dunk.
process cross between the C-41 and the C-22 for Kodacolor II
The British Journal comments: Results with this procedure are identical to those obtained following the official procedure. Having never printed any negatives processed in this C-41/C-22 sequence Michael Talbert cannot comment on the (print) quality of the negatives.
The top layer is sensitive
to Blue light and forms a Yellow dye where the developer has
acted upon it.
Oxidized Colour Developer + Dye Coupler = Dye Image. The developer will only form a dye image where the film is exposed.
The three coloured dye layers together make an opposite colour image to the subject. When printed onto colour printing paper, the colour printing paper (when developed) will again form an opposite dye image, reproducing the original colours of the subject. Apart from the contrast in the colour printing paper being higher than a colour negative film, the paper works on exactly the same principle as the negative film.
At the end of the fixing time the film consists of coloured dyes plus some soluble silver.
At the end of processing, if it was discovered that the Bleach had been omitted from the sequence, it would be possible to re-treat the film by washing off most of the Stabilizer and then re-processing, starting with the Bleach bath.
Interestingly if, by error, an exposed sheet of black and white film was to be put through a colour negative processing sequence, it would be completely blank at the end of processing. It would be be a clear sheet of film ! The colour developer would have acted upon it, making a black and white negative image but, since there would be (of course) no colour couplers in the film, the (colour) developer would be unable to also produce a coloured dye image. When the b&w film subsequently went into the Bleach bath, all of its metallic silver would be converted into silver halide, exactly as a regular colour film.
The fixer would then work exactly as with a colour film (see above) and so, following its use and subsequent wash, all the soluble silver would be removed, including the exposed black silver image, being the black and white negative image formed by the colour developer. But of course, since no coloured dye images were able to also be formed buy the developer, the total negative image would be removed and the result ? ...... a sheet of blank film !
Kodak Ektacolor Type B Film was first announced by Eastman Kodak Company in 1947 but the material was not put on sale until 1949. It was a colour negative sheet film balanced for exposure with 3200°K lamps and designed for processing by the user. The film Sizes available in 1949 were: 4 x 5ins, 5 x 7ins, and 8 x 10ins.
It was the first colour negative film in the world to incorporate coloured coupler masking. The processed negatives had an overall orange cast. The orange mask eliminated the effects of the overlapping absorbtions of the magenta and cyan dyes.
Approximate exposure times
and speeds for 1 second to 120 seconds:
The film could also be exposed with Clear flashbulbs. Guide numbers were suggested in the Kodak Data sheet and a compensating filter was recommended for exposure with clear flash to correct the colour balance. This was stated on the supplementary exposure data card packed with each box of film. It is most likely to have been a Kodak Wratten No. 81EF filter.
Also stated on the supplementary data card was the filter recommended for daylight exposures, possibly Kodak Wratten No. 85B, using a film speed of 5 ISO. I can find no mention of the shortest possible exposure time which could be used without incurring any colour reproduction errors in the resulting negatives that could not be corrected in the printing operation.
In 1949 an Ektacolor processing kit was available specifically designed for processing Ektacolor Type B film. It consisted of four chemical solutions to be made up with water Colour Developer, Stop-Bath, Hardener-Fixer (a combined bath) and Bleach.
Originally, the working temperature of the solutions and washes was 68°F, but it was found later (1950) that the film could be processed at 75°F with a correspondingly shorter total processing time.
A possible processing procedure for Ektacolor Type B film from 1949 may have been:
processing from around 1956 ~ Process B-41.
Ektacolor Print Film, introduced in 1950, was also designed to be processed in the Ektacolor Processing Kit or the later Kodak Colour Film Processing Chemicals, C-22. The two processes did not produce matching transparencies, but the differences in colour balance were small and could be easily corrected with Kodak Colour Compensating Filters.
As the baths and wash temperature was similar to Process C-22, it is very likely that the timings for the individual steps were the same.
In 1958, Ektacolor Type B film was replaced by the faster Ektacolor Type L film for Long exposures from 1/5 second (25 ISO) to 60 seconds (10 ISO) with 3200°K lamps. The previous B-41 process became obsolete and from then on process C-22 was the standard process for all Kodak still colour negative films and Kodak Ektacolor Print film.
Black & White Proof Printing Paper
By 1956 it is not mentioned in the Data sheet for Ektacolor Type B film and Kodabromide Grade 3 is recommended for making black and white prints in another section of Kodak Color Films data book of 1956.
Prints from Ektacolor Type B Film
It might also have been possible to print a small size Ektacolor Type B sheet film negative onto Kodacolor paper using the printing machines at the Eastman Kodak laboratories where prints were being made from Kodacolor roll films (see Kodacolor, above). However, I have no evidence of this ever being done and it could be that the printing machines used for Kodacolor roll film were not set up for any other kind of film than Kodacolor.
Print Film (Earlier Type)
Duplicate transparencies of any size could be made on Ektacolor Print film. Any number of duplicates could be obtained and the results on Print Film were far better than trying to duplicate an original Ektachrome or Kodachrome transparency onto Ektachrome sheet film. No sheet films specifically for duplicating colour transparencies were manufactured by Eastman Kodak until 1966 (see Ektachrome Duplicating Films).
Ektacolor Print film was marketed in various camera sized sheet films up to 11 inches x 14 inches, with larger sizes and rolls available to special order. The Film was intended to be exposed in enlargers, although negatives could be Contact printed, in the same way as when making a black and white print or colour print. It was balanced for 3200°K enlarger lamps and the colour balance could be varied by means of Kodak Color Compensating (CC) filters, or the later Kodak Color Printing (CP) filters, or a colour head fitted to a black and white enlarger.
Ektacolor Print Film could be handled under a Kodak Wratten series 10 safelight filter for about 5 minutes using a safelamp fitted with a 15 watt bulb. This was a dark amber coloured filter and the film was to be kept at least 4 feet from the direct light of the lamp.
Print Film (Later Type, 6109)
The sensitivity of the 6109 film was approximately equal to Ektacolor Paper, although Ektacolor Paper could be handled under the same safelight for a much longer time, about 4 minutes.
Filtrations for Ektacolor Print Film were similar to those on Ektacolor papers, but most negatives required a higher magenta filtration compared to the colour papers. If a certain negative had made a successful print on Ektacolor paper, its filtration would make a good starting filtration for a transparency on Ektacolor Print Film, with a stepped test exposure on the film. The film was generally about half the speed of the printing paper.
Test transparencies appeared much too reddish~magenta whilst wet, and colour balance and exposure could only be successfully assessed when the film was completely dry.
The film was not completely clear; it had a slight opaque appearance compared to an Ektachrome transparency. This created a diffuser effect when viewing a Print Film transparency.
In 1970, Michael Talbert made some 2¼ inches square transparencies by contact onto Print Film. The transparencies were intended for projection but, when projected onto a white wall, they gave an odd, diffuse, unsharp image compared to High Speed Ektachrome film transparencies. He came to the conclusion that transparencies made in this way were not suitable for projection; Ektacolor Print Film transparencies were only acceptable for display purposes, where they could be illuminated from behind.
Later, when making some 11 inch x 14 inch Ektacolor Print Film transparencies on a Beseler enlarger using Kodak Colour Printing (CP) filters inserted into the filter draw, he found that when he changed the exposure time, the colour of the Print Film also changed. To alleviate this problem, he altered the exposure by the lens aperture when the test prints were very close to the correct colour i.e. keeping the exposure time constant. He used this method of altering the exposure because of his lack of experience of making Print Film transparencies at that time (1971). But, with more experience, he became adept at filtering out the slight change in colour when changing exposure times.
Ektacolor Print Film emulsions were coated onto a thick, acetate base, approximately equal to the thickness of a sheet of Kodak black and white sheet film before sheet films were coated onto an Estar polyester thick base. In 1971, the base of the 6109 Print Film was changed to a similar (Estar thickness) base, which was thinner than the acetate base. It then became 4109 Print Film.
Ektacolor Slide Film
Although the film was first introduced in 1961, Kodak had manufactured colour print films for the motion picture industry for many years previously. Eastmancolor Print Film Type 5381, used for making cinema projection 'prints' from Eastmancolor negative 35mm cine film stock, was marketed as long ago as 1950 and, in the late 1950s, Kodak in the USA were offering to make Kodacolor transparencies from Kodacolor negatives in standard sizes, mainly 35mm, onto a film very similar to Ektacolor Slide Film.
In the UK, Ektacolor Slide Film was first listed for sale in the Kodak Professional catalogue for 1964-65, obtainable in 100 foot lengths of 35mm film. It sold at a slightly lower price than the equivalent length of Ektacolor Professional film, Type S. The base thickness was about equal to 35mm colour negative film, much thinner than Ektacolor Print Film.
By the end of the 1960s it had gained the number 5028, and in the early 1970s it could be obtained in 8 inch x 10 inch boxes of 10 sheets of film. It was also available in boxes of 15 inch x 12 inch sheets and wide rolls to special order. The sheet film was identical to the 35mm film.
The boxes of Slide Film had no instruction sheets or data sheets enclosed with the film. Having made 10inch x 8 inch transparencies on this film from Ektacolor sheet film negatives on a De Vere enlarger fitted with an Agfacolor head, Michael Talbert can say that the filtrations were similar to Ektacolor Print Film.
Print Film required 12 minutes development and Slide Film required 17 minutes development at 75°F. These times date from 1960 for Print Film and 1969 for Slide Film. Later processing sequences, dating from the mid-1970s, suggested development times of 11 minutes for Print Film and 16 minutes for Slide Film. The remaining steps for the sequence were identical to the sequence for camera films.
Print Film Additive
As an example: Add Replenisher
plus Additive to the developer after processing each batch of
Print Film. The replenishment rate was 325ccs of developer replenisher
to be added to the developer for each 1 square foot of Film
processed. Hence, having processed 4 off 8 inch x 10 inch
sheets (or 16 off 4 inch x 5 inch sheets):
In an unreplenished C-22 process, such as when processing sheets of Print Film in dishes, the 'Unit 1' 2litre size C-22 Process component containing the Developer and Stop Bath (see picture of box above), would process at least 12 sheets of 8 inch x 10 inch Ektacolor Sheet Film (6,450 square cms) before exhaustion, but only 2½ sheets of the equivalent area of Print Film before exhaustion (1,290 square cms).
The rest of the solutions in the 2litre kit, i.e. the 'Unit 2', would process at least 24 sheets of 8 inch x 10 inch Ektacolor Films, including Ektacolor Print Film (12,900 square cms).
For processing the Print and Slide Film on a regular basis, Kodak recommended a replenished C-22 system for best results. It was not advisable to develop the films giving time compensation with the development time, as used with the smaller C-22 kits when processing 35mm and roll size Kodacolor (X) films. Nevertheless, an article on the processing of Ektacolor Print Film by Ernest Gehret, published in the British Journal of Photography Almanac of 1960 (and in later Almanacs/ Annuals), gave time increases with increasing exhaustion of the C-22 Developer for up to 12 sheets of 4 inch x 5 inch Print Film processed in 1litre of developer. Gehret suggested times of development of 14 minutes for the first three sheets, to 16½ minutes for the last three sheets.
Print Film Stabilizer
Its use was recommended for all display transparencies where it gave a significant improvement in dye stability. The Stabilizer took the place of the Photo Flo rinse at the end of the process, and transparencies were given 1 minute treatment time at 7377°F before drying.
The concentrate was diluted with six parts water to make a stock replenisher solution, and four parts of the stock solution were further diluted with one part water to make the working solution. The replenishment rate was 80 ccs of replenisher to 1 square foot of Print Film processed.
Color Print Material Type C (see above, under Kodacolor paper)
Printing Paper by other Manufacturers
Agfacolor CNIII and CHIII papers were balanced for unmasked colour negative materials, such as Agfacolor negative films K and T. The orange mask present in an Ektacolor negative would have caused problems when printing onto a paper balanced for unmasked negatives. Very high magenta and cyan filter corrections would have been necessary to achieve a neutral balance. Because of the high filtration necessary, prints may have shown colour mis-matches between highlight and shadow, such as highlights too yellow and shadows too blue.
Other colour printing papers available at that time, all balanced for unmasked colour negatives include: Gevacolor, (Belgium), Ferraniacolor (Italy), Telcolor (Switzerland), and papers specifically designed for amateur colour printing, Pakolor, Synthacolor, and Raycolor (all UK made).
ICI colour negative film possessed a colour correction mask similar to Ektacolor Type B film. ICI colour negative film could be obtained for a time in the 1950s, principally by the professional user. Because of the colour correction mask in ICI colour film, the corresponding ICI colour printing paper may have been more suitable for printing Ektacolor and Kodacolor negatives.
By 1958 Ektacolor Film Type
B had been replaced by Ektacolor Type L, a new faster film for
long exposures in tungsten light (3200°K). The film was rated
at 16 ASA (ISO) for a 5 second exposure. The film was for making
colour negatives at long exposure times.
The 1958 instruction sheet, packed with the film, recommends exposures from 1/5th second to 60 seconds under 3200°K lamps.
A trial exposure meter reading was taken with the exposure meter set at 16 ASA. If the calculated exposure was much more or much less than 5 seconds (the length of time for 16 ASA), the meter was set at the film speed in the table below nearest to the calculated exposure and another exposure reading was taken.
A Kodak Wratten 81A filter (yellow) corrected the colour balance of the film for use in photoflood lighting, converting 3200K to 3400K, for a 5 second exposure at 12 ASA.
The film was rated at 20 ASA for daylight exposures at 1/5 second, with a Kodak Wratten 85B filter (yellow). For exposures shorter than 1/5 second in daylight it was preferable to use Ektacolor Film Type S.
In 1958 Ektacolor Film Type L was available in sheet film sizes (inches) of : 2¼" x 3¼", 3¼" x 4¼", 4" x 5", 5" x 7", 8" x 10".
The emulsion number found printed on the side of each box of film was also embossed on the code notched edge of each sheet of film excepting the 2¼" x 3¼" inch size.
Kodak Ektacolor Type L film
was replaced by Kodak Ektacolor Professional Type L film in 1963.
Ektacolor Film Type S was a sheet film colour negative material introduced by Eastman Kodak in 1956 balanced for exposures with clear flashbulbs (3800°K 4000°K), at 32 ASA (ISO).
Daylight exposures were made with a Kodak Wratten filter 85C (bluish) with an exposure rating of 25 ASA. The film was very similar to the then new Kodacolor roll film, and the daylight exposure guides mentioned in the data sheets for either film were identical.
In 1956, Kodak Ektacolor film type S was designed for exposures of 1/25 second or shorter. By 1959, the maximum length of exposure time had been increased to 1/10th second. Exposures longer than 1/10th second would have caused errors in the colour balance of the film which could not have been corrected in printing.
The exposure for an average
subject in bright sunlight was 1/50th second at f/11.
In 1956, the sheet film sizes available were the same as Ektacolor film type L.
By the late 1950s, Ektacolor Film Type S was available in the U.S.A. to professional users in 35mm and other widths. Supplied in long rolls, it was for use in school, identification, and portrait photography. This bulk roll film version was known as Kodak Ektacolor Film without a type designation.
By 1961, the same film was on sale in the U.K. to approved professional customers in 35mm bulk film format. The Kodak Professional Catalogue for July 1961 lists long lengths of 99 feet, 200 feet, and 400 feet bulk film. The film was said to have the same characteristics as Kodacolor film and, presumably, the same speed 32 ASA (ISO).
Kodak Ektacolor Type S Film was replaced by Ektacolor Professional Type S Film in 1962.
In 1962, a new version of Kodak
Ektacolor Type S film was marketed for professional photographers.
Ektacolor Professional Film Type S was very similar, but not identical, to Kodacolor X film. While Ektacolor Professional film was aimed at the professional market, Kodacolor X was principally an amateur photographers colour negative film, balanced for clear flash illumination and designed to be printed by photofinishers making en-prints and moderate sized enlargements. Ektacolor Professional film was often processed and printed by the photographer in his own darkroom, using enlargers with a filter drawer or colour head. Correctly exposed Ektacolor Professional Type S negatives generally required yellow and magenta filters for printing, whereas, Kodacolor X negatives, being slightly yellower, or redder in colour than an Ektacolor negative, frequently required the use of cyan filters to balance a colour print.
If Kodacolor X film was exposed to daylight with a Kodak No. 85C filter over the lens, the resulting negatives were very similar in colour balance to Ektacolor Professional film Type S negatives and could be printed with yellow and magenta filters.
As it was possible that amateur photographers might expose their Kodacolor X film negatives to widely differing lighting conditions, the photofinishers who printed the resulting negatives compensated for the variations in colour temperature by means of their automatic colour printing machines. To assist the photofinishers in coping with this range of variation, Kodacolor X film, and the earlier Kodacolor film, were balanced for 3800°K, (clear flash bulbs), approximately mid way between daylight and tungsten illumination.
Prints made on automatic colour printing machines may have had slight colour mis-matches regarding highlight to shadow differences, (magenta highlights, green shadows as an example), but generally Kodacolor X and Kodacolor films were capable of giving a pleasing balance with most subjects. As Ektacolor Professional Film was balanced for daylight, it was to be expected that a slightly higher degree of colour accuracy was obtainable with subjects exposed in daylight conditions compared with the Kodacolor films. However differences were slight and a lot depended on the quality of the final print.
In early 1963, a 120 size roll
film Ektacolor Professional Type S Film was made available.
Like the previous Kodak Ektacolor Film, (see above), the Type S professional emulsion was also made in 35mm size and supplied in long rolls. The Kodak Professional Catalogue for 1964, (for the U.K.) lists Ektacolor Professional Film Type S in 120 rolls, coded CPS 120 and bulk 35mm film in 100 ft. and 400 ft. lengths.
In 1966, the speed of all Kodak camera colour negative films were increased by 1/3 of a stop, making Ektacolor Professional Film Type S the fastest colour negative film in the world at 100 ASA (ISO). In the U.K., by 1970, an additional size of 70mm film was made available in 100ft lengths. Two years later, another addition was 35mm size film in 36 exposure cassettes. 220 size film was listed in the Kodak U.K. Professional catalogue by 1971. In the U.S.A., 220 and 620 size rollfilms were mentioned in the data sheet for Type S Professional Film in October 1964.
Near the end of 1963, Eastman-Kodak introduced a faster long exposure colour negative film to replace Kodak Ektacolor film Type L. (see above) It was designed for exposures in tungsten lighting at times from 1/10 second to 60 seconds.
Like the previous Ektacolor Type L film, the speed of the film depended upon the exposure, and the exposure was calculated in exactly the same manner as with Ektacolor Type L film.
Daylight exposures were possible at 1/10 second with a Wratten 85 (yellowish) filter, and exposures under Photoflood illumination could be made using a Wratten 81A (yellowish) filter at 1 second. Both filters cut the film speed to 50 ASA (ISO).
Although not mentioned in the data sheets or the instruction leaflets packed in the film boxes, it was also possible to expose Ektacolor Professional film Type L for exposures as long as 2 minutes. In the Kodak Color Data book Applied Color Photography Indoors (E 76), the section on exposure, describes that a 2 minute exposure can be made at a speed of 16 ASA through a CC 10R filter this is a Colour Compensating filter of 10 Red density. This information is similar to the longest exposure that can be made on Ektacolor Type B film using a film speed of 2 ASA. (see above)
Negatives made on Ektacolor Professional film Type L exhibited slightly higher contrast than negatives made on the Type S professional film.
The author remembers exposing some sheets of 5 x 4in. Professional Type L film in daylight conditions without a compensating filter to make use of this contrast increase. The negatives possessed a red cast, but on printing them on Agfacolor MCN III type 7 paper, there was only a slight miss match of colour balance (red shadows, cyan highlights).
In November 1963, Ektacolor Professional film Type L was made in sheet film sizes of 2¼" x 3¼", 3¼" x 4¼", 4" x 5", 5" x 7", 8" x 10" and 11" x 14" (all inch sizes). There was also a half plate size (4¾" x 6½") mainly for the U.K. market.
In 1966, the film speed was increased to 100 ASA for 1/10 second exposure and all the ASA speeds in the table above increased by 1/3 of a stop.
Ektacolor Professional film Type L was never made in roll film or 35 mm sizes, and was replaced by Vericolor Professional film 4108, Type L in 1975.
All Ektacolor and Ektacolor Professional films, not Ektacolor Type B film, were processed in Kodak Color Film Processing chemicals, Process C-22. In the U.S.A., a Kodak Color Processing Kit, Process C-22 was available in a 1 gallon size. In the U.K. kits of C-22 chemicals were sold in 600ccs, and 2 litre sizes containing the five chemical baths and the Photo-Flo solution for the final rinse. Larger sizes, up to 100 litres, were available in individual chemical packings.
When using the 600ccs kit, the Developer and Stop-bath had to be replaced after every four rolls of 120 size film developed. The development time, starting at 14 minutes, was increased by 2 minutes for every 120 size film put through the developer, and thus varied from 14 minutes for the first roll to 20 minutes for the last. The Stop-bath time was not increased nor were any of the other solution timings for the life of the kit. The Hardener, Bleach, Fixer and Photo-Flo rinse, had twice the capacity of the Developer and Stop-bath.
From the authors experience of processing Ektacolor and Kodacolor films in many of the 600 ccs kits, the Stop-bath was frequently overworked and it was far better to make up the last solution, the Photo-Flo rinse, separately for each processing session. This gave much cleaner negatives ! But provided one worked methodically, and was very careful not to contaminate one solution with another, these small sized kits could provide negatives of a very high quality.
From 1975, the four solution Process C-41 replaced Process C-22 giving a faster total time of 24½ minutes
Since Ektacolor Type B film was introduced in 1949, Eastman Kodak have recommended refrigerated storage for all types of Ektacolor film at 55°F (12.8°C) or lower. Better still, freezing the sealed, unexposed film in a freezing unit would delay the changes in the films characteristics, such as speed and colour balance, for a very long time. But even at this low temperature, the film was likely to change very slowly and it was always advisable to use the film before the expiry date stamped on the box.
Kodacolor film and Kodacolor X film did not require refrigerated storage.
Kodak Vericolor colour negative films were introduced in the USA in 1970. They were intended for rapid processing in the Kodak Versamat Model 145 machine, the total dry to dry time being around one fifth of the (then) C-22 wet processing time for Kodacolor and Ektacolor films. Vericolor film had its own chemical baths and could not be processed in C-22 chemicals. The films were similar to the Ektacolor Professional films at that time.
Types of Vericolor Film available in the USA in 1972
Type S and Type L sheet film were coated on a polyester base. In the U.S. A. both types of sheet film were available in 4x5inch and 5x7inch formats (10 sheet boxes), designated, Vericolor Type S 4105 and Vericolor Type L 4106.
Types of Vericolor Film available in the UK in 1972
Approximate bath sequence of the processing steps:
The Versamat 145 machine could process sheet film, roll film and 35mm film working at a speed of 3feet per minute. Kodak manufactured other types of Versamat machines, but the 145 model was the only one capable of processing Vericolor films.
The chemicals were obtainable in packs to make up 25gallons of each solution, except for the fixer. Kodak Color Film Liquid Fixer, was used for the process, this fixer being common to the C-22, E3 and E4 processes. The Colour developer was made up of Developer Replenisher and Developer Starter. To make the working solution, the Starter was mixed with the Replenisher and the working strength developer solution was then replenished with the developer replenisher alone.
At the time Vericolor films were marketed, very few colour laboratories in the U.K. would consider purchasing a Versamat machine to process Vericolor films alongside the then, current, Kodacolor and Ektacolor films. It was known that the Flexicolor process (C-41 process), with new amateur and professional films would, at some stage, replace the existing C-22 films and process. Indeed, Kodacolor II film was already on the market. Thus, it was hardly worth while investing in a process which would become obsolete in another two or three years time, although it was pointed out at the time that the Versamat machines could be modified to take the new Flexicolor chemistry. The cost of a Versamat Color Processor Model 145 in 1973 was over £10,000. This included three service calls and free maintenance for one year.
Vericolor Type S and Type L films were replaced by Vericolor II Professional films, Type S and Type L in 1974. By 1975, the range of Kodak Vericolor II Professional films were gradually replacing Ektacolor Professional films for camera use.
When Eastman Kodak began to sell Kodacolor Film in various roll film sizes to the general public in March 1942, all processing and printing of the new film was done internally at Eastman Kodak, Rochester, N.Y.
Prior to marketing Kodacolor Film in its various roll film sizes, a method had to be devised of printing thousands of small colour pictures per day from colour negatives. Eastman Kodak had already started a colour print service for making colour prints from Kodachrome transparencies. With regard to correcting the colour balance of the print, printing from a colour transparency is a simpler task than if the same print is to be made from a colour negative. Colour casts on transparency films can be easily seen by the printer, and a correction can be made before printing. However, it is much more difficult to see a colour cast on a colour negative, because the negative appears in reversed colours.
The 1599 printers were equipped with triple negative carriers, and required the negatives to be cut into strips before printing, presumably into strips of 3 or 4 depending on the number of exposures per roll film.The triple negative carriers allowed the operator to change one negative while another two were being exposed to the paper. Three prints of equal size were printed across an 11 inches wide roll of paper in parallel rows. After processing, and before the prints were cut and separated into their individual orders, they were examined by an experienced operator, and any prints not up to standard were marked with a correction and the negatives were returned for re-prints.
Eastman Kodak designed equipment for slitting and cutting the rolls of exposed paper into 3½ in wide prints.
The Eastman Kodak 1599 printer was not made available to any other photofinishing companies, possibly because it was complicated to set up, and was designed to print only from Kodacolor negatives and only onto Kodak colour printing paper (though no doubt it could have been used with other makes of film and colour paper with appropriate settings).
In 1949, Eastman Kodak introduced Ektacolor Type B sheet film, and it might have been possible to print small size sheet film negatives using 1599 printers onto Kodak colour paper. There is no evidence of this ever being done and it is possible that the 1599 printer was not set up for any other kind of film than Kodacolor.
The colour negative was exposed through individual red, green and blue filters, (three separate exposures). The exposures were each the same length of time due to the fact that the final print would show a change in colour if one of the exposures varied in time compared to the other two. At that time, there was no way of altering the exposure time to compensate for any colour casts on the negative film. The intensity of the printing light was adjusted automatically by light sensitive photocells to give the correct exposure to compensate for underexposed negatives, or overexposed negatives. Thus the total time of the three exposures was the same for a thin, underexposed, negative as it was for a thick, overexposed, negative.
This method of making three exposures was known as Tri-Color Printing. There seems to be very little written information on how Eastman Kodak operated their printers in those early days but below is an attempt to show how there may have been three distinct methods (phases).
Method (as from 1942)
Very simply, by way of example, say the negative to be printed was evaluated to have a green cast. Without correction, the resulting print would look magenta. Therefore a magenta filter would have to be placed in the printer to remove the colour cast. Remember that the green exposure cannot be altered to correct for the colour cast.
Estimating colour casts on every single negative must have taken up much time. Therefore, it was decided later to judge only one negative per roll of film for colour casts, and then print the whole roll using the same filter correction.
One drawback with this system was that the individual frames on the same roll of film may not all have been taken in the same lighting conditions, and hence the negatives may have had different colour casts.
All roll films were made slightly longer than was necessary for the standard number of exposures per roll, irrespective of the size of film. Photographers were advised not to expose or fog this part of the film. Before processing to a colour negative, this extra portion of film was exposed by the laboratory to a standard reference colour patch. After processing the film, and before printing, the colour densities on this reference patch were measured and evaluated. Each negative was then punched with a series of very small holes along the extreme edge of the film corresponding to the results of the colour density measurements. The size and location of the small holes automatically regulated the various colour printing filters to correct for the colour cast(s) of the negative being printed. This method, as presumably the first method, took into account the emulsion deviations of the various batches of Kodacolor film.
By perhaps the mid-1940s, the Kodak 1599 printer was sufficiently advanced to incorporate photo-electric cells to automatically compensate for colour casts of Kodacolor negatives. In common with other automatic colour printers, when the settings on the 1599 colour printer had been adjusted so that the printer produced a good print from a 'standard' test negative exposed to an average outdoor subject with no colour bias, the vast majority of all subsequent negatives would print satisfactorily, or nearly so.
The photo-electric cells measured the light transmitted from the negative for each of the red, green, and blue exposures (additive printing) and terminated each exposure when the amount of colour striking the printing paper (time x intensity) was the same as was expected from the 'standard' test negative. This was done by varying the intensity of the light behind each filter rather than varying the time of exposure; the exposure time was kept constant so as to not upset the reciprocity characteristics of the paper. The exposure intensity of the light behind each filter varied automatically according to the colour cast(s) of the negative being printed, but as long as the total intensity of each of the three light colour exposures remained the same as the total intensity of each colour as required by a 'standard' negative, a good print was likely to result.
This method of assuming customer
negatives would integrate to grey without a colour bias, was
used for printing Kodacolor negatives on the 1599 printers for
almost 20 years.
|Kodacolor Processing and Machine Printing Comes to the UK ~ 1958|
|In May 1958,
Miniature Camera Magazine (MCM) reported:
Kodak have opened an entirely new processing station at Hemel Hempstead to meet the growing demand for colour photographs, particularly those made from Kodacolor roll films which were released on the British market last October. It is also designed to take care of the processing of 35 mm., 16 mm. and 8 mm. Kodachrome and this work will be gradually transferred from the present Harrow processing department to Hemel Hempstead. When completed, this plant will be a completely self-contained production unit with a staff of nearly 1,000 people.
1959, MCM reported:
Colour Prints For All; A Visit to the new Kodacolor Processing Station at Hemel Hempstead.
Modern Camera Magazine recently had the opportunity, at the invitation of Kodak Limited, of visiting their new colour processing plant at Hemel Hempstead devoted exclusively to the processing of several colour materials now provided by this company. The demand for these is so large that it had been found necessary to start work at the factory before it was fully completed so that at the moment all sections are not in use. At the present time, for example, most of the Kodachrome films are still processed at Harrow, but ultimately all colour processing will be done at Hemel Hempstead. Some idea of the size of the building can be gathered from our first photograph.
Although Kodachrome in its 8, 16 and 35mm forms (sheet film Kodachrome is no longer made, its place having been taken by Ektachrome) is the best known of the Kodak colour products, the sales of Kodacolor, a colour negative film designed for print making, are rapidly increasing. The whole of the developing and printing of this material takes place at Hemel Hemp-stead. Colour prints are also made there from Kodachrome 35mm transparencies and special provision has been made at the new plant for the instruction of staff in colour processing, so that outside organisations, such as the well-known photo-finishing firms in various parts of the country, may be able to enter this field. This form of training is most important for it is not the policy of Kodak Limited to process Ektachrome, which they hope will ultimately be processed either by the consumer or by approved developing and printing establishments.
Have you ever made a mistake in addressing your Kodachromes to Kodak or omitted to add your own name and address? Some seven thousand people did last year, although actually this represents a very minute proportion of the total number of films sent in. Satisfying the customer is one of the main aims of this plant and we were interested to see the various steps taken to prevent such films being entirely lost to the user.
In cases where films have been sent in without any obvious means of identifying the sender, after processing they are always examined to find whether, for example, there is a photograph of a motor-car on which the registration letters and number can be seen, whether there are other indications of the places in which the films were taken, the types of subject, or indeed anything unusual. These entries are made on specially printed forms with columns for various indications and the film then goes to a kind of "dead letter office" awaiting enquiries. If a customer complains that he has not had his film returned another special form is sent to him with certain specific questions and in a considerable number of cases the sender is traced by comparing the film with the "dead letter" form. The special museum, if it may be called such, at this dead letter office, is well worth a visit and shows what strange things people will do at times in the way of wrong treatment. For example, Kodachrome films all have to be processed in continuous strips, each length of film being carefully spliced to the previous length for the continuous processing machine. This continuous running is essential, since processing Kodachrome is a very complex procedure and, if in spooling up, before processing, a break in the film is discovered, a proper cemented splice is made. However, it is not unusual to find that the two ends of the broken film have been pinned together or even stapled by the customer, and often the two ends are roughly joined with adhesive tape. If joints of this kind were allowed to get into the machine they might cause serious damage.
The careful preparation and testing of the necessary processing chemicals before they are pumped into the huge tanks from which they are circulated to the processing machines, occupies an important section of the building. So far as the Kodacolor print making service is concerned, there are two main divisions of work ~ (i) the processing of the colour negative and (ii) the making of the print. After the colour negative comes from the processing machine it is carefully examined visually and marked frame by frame so that grossly over, or under, exposed negatives, which would not make satisfactory prints, can be eliminated. The negatives then go to automatic printing machines which select the correct printing filters and automatically determine the exposure required. This general integration of the negative for exposure and colour balance is perfectly satisfactory with average subjects but, like the integration method of determining exposure for monochrome work by photo-electric meter, it is not always right for exceptional subjects. Thus when the finished prints come through (they are all printed on a continuous band) another inspector marks those prints which require re-printing in adjusted conditions, so that before the final batch of prints reaches the consumer, the best has been made of every negative.
We were greatly impressed by the care and discrimination used throughout the processing of colour material and this probably accounts largely for the high standard of Kodacolor prints now being turned out.
Michel Talbert comments: in these early days, some prints were of poor quality due to their negatives being of scenes with an imbalance of colours compared to a theoretical 'average' scene i.e. they suffered from what the trade described as 'subject failure'. The classic example is a girl in a white dress sitting on a lawn the dress comes out pink from an automatic printer that has no means to recognise that there was an 'excess' of green within the original scene and compensated for that 'excess' by applying additional magenta filtration. Such automatic printers integrated all the colours coming through the negative and applied a printing colour filtration that would make the resulting mix of image colours in the final print integrate to pure grey, regardless of whether the original scene colours would have actually integrated to grey. On the later generation of printers, when the operator spotted one of these 'subject failure' negatives, he pressed an L1 button, and this would make the printer use a lower correction, i.e., the negative wasn't integrated to 100% grey, and this took care of 'subject failure' negatives. There may also have been an L2 button, for even less integration of scenes with severe subject colour failure.
The Machine Printer Type IVC
was originally based on the Eastman Kodak Velox Rapid printer
used in the USA. It was an additive printer, goiving sequential
exposures through red, green and blue filters.
After the Type IV, the Kodak Type S.1 printer was the next model. This was a subtractive 'white light' printer.
White Light printers started off with a White Light exposure i.e. no filters in the light beam. While the white light exposure took place, the negative was assessed by the printing machine. When the machine decided that the red exposure must end, a cyan filter came across the light beam, the printer carried on giving the exposure through the cyan filter which was equivalent to the green and blue exposures with tri-colour additive printing. The green exposure ended with a magenta filter sliding across the light beam, but the blue exposure carried on, since the cyan and magenta filters were effectively a blue filter. The blue exposure ended by a shutter on the printer cutting off all light to the paper.
The blue exposure was usually
the longest, because of the red/yellow masked negatives, which
had a high density to blue light. Obviously, the red exposure
was the shortest, green somewhere in between.
The exposing light was always kept on, the shutter opening only when the exposure was being made, like a camera. White Light printers were much faster than the previous additive tri-colour printers, partly because of the white light exposure at the beginning with no filter in the light beam, where the red, green and blue exposures took place simultaneously. The trouble with tri-colour printers was that the three exposing filters were always very dense, which increased the overall exposure times drastically.
who is really interested in machine colour printing is recommemnded
to obtain a copy of Jack Cootes book, Photofinishing
Techniques, published as long ago as 1970 by Focal Press.
Its one of the very, very few books written on Machine
Printing. Some basic information from the Jack Coote book can
be read here:
Every colour printing paper was susceptible to what is known as Reciprocity Failure. If a print was exposed for 5 seconds at f5.6, the colour balance and density should have equalled that of another print given a longer exposure time at a smaller aperture, e.g. 40 seconds at f16. Unfortunately this was not the case, and the second print would have been under-exposed and with a different colour balance, due to the paper's Reciprocity Failure.
With regards to colour prints made in Machine Printers; low density, i.e under-exposed, negatives required much shorter exposure times through the printer's red, green and blue filters than was the case with high density, over-exposed, negatives that required relatively longer exposure times. With such printing time variations, the printing paper's Reciprocity Failure became a problem. In addition, an under-exposed negative, printed with a short exposure time, may have produced a print with a green cast. An over-exposed negative, requiring a much longer printing exposure time, may have resulted in a print with a magenta cast. It may also have been lacking in density. Both prints would have been considered unacceptable. To overcome this problem, the first colour printers that were used by the Eastman Kodak Company from 1942 (called the 1599 printer) overcame this problem by varying the intensity of their exposing light. The 1599 exposed all prints at a fixed exposure time. An under-exposed, thin, negative took as long to print as one which was over-exposed, avoiding shortening or lengthening the exposure times would have caused the three colour sensitive layers re-act differently to one another, producing colour casts in the prints due to the printing papers reciprocity failure.
By the mid-1950s Machine Printers were being manufactured with a facility known as Slope Control, which enabled the Type IVC Machoe Printer to operate using variable time exposures through its three colour filters, rather than using the Type 1599 variable light intensity method.
If calibrated correctly, the Slope Control facility in a Machine Printer compensated for colour balance and density changes from negatives which were from 2 stops under-exposed to 2 stops over-exposed, correcting the green cast by automatically giving a longer Green Exposure (for an under-exposed negative), or decreasing the Green Exposure (for an over-exposed negative). The Slope Control setting would also have applied any necessary correction to the print density. Reciprocity Failure colour balance changes varied according to the make of colour printing paper.
Outside the +/- 2 stop exposure range capability of the 'Slope Control', the colour balance would have had to be corrected by using colour correction buttons on the Machine Printer. But any negative outside the +/- 2 stop exposure range might equally have been considered of such poor quality, especially when under exposed, that the Machine operator might have simply declined to print it. In this case, the customer would have had to return the negative with instructions to 'Print Regardless', if the image was of such importance that obtaining even a poor quality print was better than no print at all.
Correcting the density of under and over exposed negatives could also be done by the Printer operator using +1, +2, (or more) buttons on the printer (with dense negatives), and using -1, -2, (or more) buttons (with 'thin' negatives). Operators were taught to use the 'Plus' buttons with dense negatives and 'Minus' buttons with thin ones.
Very few negatives contained the theoretical one third exact proportion of red, green, and blue colour component dyes and experience showed that a Machine Printer operating at a lower level of integration (than theoretically correct) would produce acceptable prints from negatives of subjects coming in between scenes which would integrate exactly (to grey) and to scenes bordering on 'Subject Failure' i.e. scenes with an excess of one colour or another. By setting a lower level of integration it was found that there was more chance of the Machine Printer producing a high level of acceptable prints from a wider range of negatives. This applied especially to Machine Printers where the negatives were printed only once and no test strips were made. However, below 100% integration was just as valuable on Machine Printers where the price level of the prints produced allowed at least one test strip. The nearer the first test strip was to the correct colour and density, the easier and quicker it was to make a good final print.
Pictures of landscapes were common 'Subject Failure' negatives, contained large areas of green landscape that meant there was a large area of excess magenta in the negative. As explained above, the landscape area would have been both lighter than the sky and maybe twice the sky area (the sky might have been only one third of the total negative area). Hence, for both reasons, when the Machine integrated the light passing through this type of negative, the tendency would be for the Machine to over-correct the magenta content of the negative by (incorrectly) increasing its green exposure so as to 'correct' what it assessed would otherwise be an excess of green in the final print. The resulting prints from landscape subjects were noticeable by the pink clouds in the sky. This was a fairly common case where the Machine Printer could not tell if the colour cast in the negative was due to a technical error of, say, faulty processing (needing correcting), or was the actual colour of the subject (not needing correcting).
By operating a Machine Printer at a lower integration rate, many of these subject failure landscape negatives would produce first time acceptable prints.
Acceptable prints, say up to a size of 6 inches x 4 inches and 5 inches square, printed at a laboratory dealing mainly with amateur photographers work where the negative was printed without any test strip first, the colour balance could actually vary from ideal by around 10 units of Kodak Colour Printing filter cast in any direction. Most prints could have been improved by hand printing on an enlarger, but in the case of the best Machine prints made from correctly exposed negatives, they could be improved only slightly and, in a few cases, not at all.
The colour balance of prints made from very over, and under-exposed, negatives would have greater colour casts than a 10 unit Kodak Colour Printing filter. Standards varied considerably according to the laboratory and price per print.
On a personal note, Michael Talbert made many 6 inch x 4 inch machine prints on a Pako printer, and found that the general public would accept quite wide variations in the colour balance of their prints, but the density of the print had to be correct, or very nearly so.
Type I paper
The emulsions were coated onto a fibre base support, with an unglazed gloss surface. The contrast was normal, or medium. The equivalent Kodak black and white papers manufactured at that time were (in the U.S.A.) Kodabrom F2 white, glossy, smooth, normal, and (in the U.K.) Bromide BG2, Nikko *(see footnote, end of page) medium. The base weight of Kodacolor paper was Medium, in between single and double weight.
With Kodacolor Type 1 paper, the magenta dye faded rapidly in the processed prints, causing the white borders and eventually the image aitself, to turn yellow. The magenta dye coupler was much improved in later versions of Kodak colour printing papers.
III Type 1348 paper
This new arrangement of layer order improved the visual sharpness of the print. As the red sensitive, cyan dye forming layer was now on top, this now became the sharpest layer. It had been noticed as long ago as 1928, that the cyan dye layer provided most of the apparent sharpness of a tri-pack material, partly because it often forms the heaviest dye deposit.
There is some doubt concerning the information on the two types of Kodacolor Type III papers i.e. Type III and Type III 1348. In the literature, other sources suggest that it was Kodacolor Type III paper (in 1952) that was made with the reverse order of sensitive layers. My own research has failed to confirm this, though there was a change made to Kodacolor film in 1949 that may be at the root of this confusion. In 1949, a new version of Kodacolor film was marketed incorporating an orange/red masking layer to improve the colour rendering of prints. Prior to this, the two earlier films were of the unmasked variety, though the second type included a contrast mask in black and white.
It is probable that, in 1949, Eastman-Kodak changed the layer sensitivity of its Kodacolor paper, increasing the speed of the blue sensitive layers, to compensate for the high density of the orange masking layer in the new Kodacolor film. An orange masked Kodacolor negative printed onto a paper designed for unmasked colour negatives would have otherwise needed a long blue exposure to prevent a strong blue/cyan cast caused by the mask. However, I can find no firm evidence that Eastman-Kodak actually did change the layer sensitivity of the paper at that time.
Eastman-Kodak knew that the green and blue layers would have to be increased in speed (sensitivity) because of the orange mask as long ago as 1946, as was mentioned in the P.S.A. Journal (Photographic Society of America), February 1947, where Hanson and Vittum described the forthcoming masking system and how it was to work for Kodacolor ("Colored Dye-Forming Couplers In Subtractive Color Photography. It was presented at the PSA Convention at Rochester N.Y. in November 2nd, 1946. It became Eastman-Kodak communication No. 1106).
The above types of Kodacolor papers were used internally by Eastman-Kodak for prints and enlargements in their own laboratories and were never sold to any other photo finishers or photographers. During 1954, the US Supreme Court ruled that the Eastman Kodak Company were required to release technical information on the printing and processing of Kodacolor films and papers to colour processing laboratories and photofinishers in the USA who wanted to handle the processing and printing of Kodacolor film.
Color Print Material, Type C
The Kodacolor print dates from 1952 and the Agfacolors date from 1954.
On the back of the Kodacolor
print it says:
The two Agfacolor prints were made in 1954. They are most likely to have been printed on Agfacolor CN III paper. They have Agfa printed faintly on the back at various intervals. The film the pictures were taken on would have been Agfacolor CNT film for Daylight rated at 10 to 12ASA (ISO) producing an unmasked colour negative.
The difference between the colour balance of the Kodak and Agfa prints is quite considerable. The Kodacolor print suffers from Thermal Yellowing very badly, a fault inherent in the four early Kodacolor papers.
Thermal Yellowing was caused by heat and humidity reacting with the dyes in the print. It was also caused by the unused colour couplers left in the emulsion layers reacting with the print dyes, mainly the magenta coupler. For instance, in this case, where the colour Magenta is not generated by colour development, there are unused colour couplers left in the emulsion after processing the print. Very early Kodacolor prints turned green as the magenta dye faded faster than the other dyes. Thermal Yellowing also caused the borders of the print to turn yellow rapidly.
This Kodacolor print does retain some traces of pink in the flowers on the left and green in the lawn on the right. It is said that there are now no Kodacolor prints made between 1942 and 1954 which remain in a reasonable condition.
Kodak Color Print Material Type C (introduced in 1955), brought about a marked improvement in Thermal Yellowing but the cyan and yellow dyes in Kodak prints made in the mid to late 1950s faded quickly, giving the prints a magenta cast. Much the same could be said about Agfacolor prints made during the same period. Very generally, with prints made between 1955 and 1959, Kodak colour prints now look magenta, while Agfacolor prints now look red. There are exceptions, depending on how and where the prints are stored.
Kodak Ektacolor papers introduced from 1958 to 1965 resulted in prints with much improved dye stability, even greens, and Thermal Yellowing was virtually eliminated. It is the authors opinion that the equivalent Agfacolor papers were less stable, and that Agfacolor MCN III Type 4, introduced in 1972, was the first Agfacolor paper to approach the dye stability of Kodaks Ektacolor papers.
As from 1955, Kodak colour printing materials, and the corresponding processing chemistry, were made available for sale to photographers, photofinishers, professional processing laboratories, or anyone else - but this applied only in the USA.
In the UK, Kodacolor Film was first sold in 1957 but all processing and printing was done by Kodak Ltd. Kodak did not release the processing chemicals and printing paper for general sale to anyone in the UK until 1959.
The change of name from Kodacolor paper to Ektacolor paper, post-1955, is thought to have occurred when it became possible for photographers to self-process Ektacolor Type B film and self-print their results onto the new (in 1955) Kodak Color Print Material Type C. The Type C material subsequently (1957-58) became known as Ektacolor paper (see below). At the time of the name change from Kodacolor to Ektacolor, the 'Koda' prefix is thought to have referenced print materials which could only be processed by Kodak, while the 'Ekta' prefix referred to materials which could be self-processed by the photographer, if he wished his results to be all his own work.
In 1959, the emulsion layers of Ektacolor Paper Type 1384 had sufficient hardness to enable processing to be carried out at 85°F, thus reducing the overall wet processing time to 25 minutes in the P-122 processing chemicals. The Developer was used at 85° +/ ½°F, and the rest of the chemicals and washes were used at 8387°F.
However, there is some uncertainty here, as the Ektacolor paper which could be processed at this higher temperature may have been a new paper, designated, Ektacolor Paper, Type 1502, introduced in 1959.
Type 1502 was followed by Ektacolor Paper Type 1583 in 1962. In 1964, in the UK, the paper was obtainable in sheet sizes from 8½ x 6½ inches up to 30 x 40 inches, and in rolls up to 40 inches wide by 10 metres long.
In the UK, Ektacolor paper Type 1583 was replaced by Ektacolor 20 paper (see below) in 1966, but it was still listed for sale in the Kodak Limited UK Dealers Catalogue for 1966 to 1967. It is likely that all types of Ektacolor paper were manufactured in the USA at Kodak's manufacturing premises at Rochester New York, and then imported into the UK.
The colour balance of Ektacolor papers varied slightly from one emulsion to another and the white light filtration or the tri-colour exposures had to be altered when changing from one batch of paper to another. When using the earlier types of Ektacolor papers, the user was expected to expose a print on the new batch of paper and then compare the colour balance with a similar print, from the same negative printed on the old batch of paper. The print on the new paper then gave the colour balance and density difference between the two papers. The filtration and exposure for white light printing or the tri-colour exposures on the new print were then altered to match the colour balance of the old print.
By the early 1960s, certainly by 1962, Eastman Kodak gave the user a guide as to the difference between the various emulsion numbers of Ektacolor papers. Stamped on each label were Arithmetical Factors for Tri-Colour (additive) printing and a Filter Pack Adjustment and Speed Factor for White Light (subtractive) printing. The figures given were only an approximate guide to help the user make filter changes or change exposure times in the right direction. They were no help in giving a starting filtration to an unknown negative.
20 and Ektacolor 20 RC paper marketed in the USA from 1964 to
The first Resin Coated (RC) colour negative printing paper was marketed as Ektacolor 20 RC paper Type 1822 in 1968. The 1822 designation was essentially the Type 1870 emulsion extrusion coated in polyethylene. The paper was manufactured with a High Gloss surface which eliminated glazing, and the surface was coded F, similar to the American black and white papers at that time.
Later in 1968 an improved version was introduced as Ektacolor 20 RC paper, Type 1910. This paper was also offered in two additional surfaces, Silk, coded Y, and Lustre, coded N, again similar the black and white papers of that time. The surface textures were almost identical to the equivalent Y and N black and white papers, such as Kodabromide and Medalist.
All Ektacolor 20 and Ektacolor 20 RC papers were processed in Ektaprint C chemicals, taking a total of 22 minutes at 85°F wet processing time.
Various literature suggests that the processing times were reduced for the two types of Ektacolor RC papers, notably (and logically) the last wash time, but Michael Talbert has been unable to find any actual Eastman Kodak processing sequences or printed literature where this was included when using Ektaprint C chemicals.
None of the Ektacolor 20 papers could be processed on the Rapid Color Processors using CP5 chemicals. These papers were mainly used in D&P laboratories in the U.S.A., and gradually replaced the older Ektacolor paper (see previous, above). Professional photographers who printed and processed their own colour prints, and Professional Colour Laboratories whose work was exclusively processing and printing professional photographers negatives, used Ektacolor Professional paper (see below).
The Ektacolor 20 RC paper Types 1822 and 1910 were replaced by Ektacolor 47 RC paper in 1970.
Ektacolor 20 and Ektacolor
20 RC paper marketed in the UK from 1966
Much of the information given in the instruction sheet was identical with the instructions for Ektacolor Commercial paper. Two differences were that (i) Ektacolor 20 paper could not be processed on the Kodak Rapid Color Processors, and (ii) the exposure factors given on the sealing label of each packet or box only related to different batches of Ektacolor 20 paper, and could not be used to switch from one make of paper to another, such as from Ektacolor 20 paper to Ektacolor Commercial paper.
Kodak Brightening Additive could be used with Ektacolor 20 paper, mixed with the Formalin Fixer, to make the colours more brilliant, increase the print contrast, and give extra stability to the dye image. However, since the smallest quantity of Brightening Additive which could be obtained from Kodak UK was 3 UK gallons, it is unlikely that many amateur colour printers purchased it. The chemical was more likely to have been used by the professional D&P laboratories.
Ektacolor 20 paper was
intended for processing in Ektaprint C chemicals, with a
total wet processing time of 22 minutes at 85°F.
By 1970 the paper was being
coated on a Resin Coated base and designated Ektacolor 20 RC
paper with a highly glazed surface. It was obtainable only in
rolls for the photofinishing trade.
Ektacolor 20 RC paper was replaced by Ektacolor 37 RC paper in late 1971.
Commercial Paper (see
box picture in this Section, below)
Ektacolor Commercial paper was available in sheet sizes from 6½ x 8½inches to 30 x 40inches and wide rolls up to 40inches wide.
It was replaced by Ektacolor 37RC paper in 1972 although for a short time both products were being sold concurrently.
The paper was originally designed for the 7 bath P-122 Process at 75°F, but later could be processed in the 6 bath P-122 chemistry (U.S.A.), the 5 bath P-122 chemistry (USA and UK), and Ektaprint C chemistry. In 1963, Professional was the first and only colour negative printing paper which could be processed in 7 minutes on the then, new, Kodak Rapid Processors i.e the H11L and 16K, using CP-5 chemistry.
It was replaced by Kodak Ektacolor 37RC in 1972 although for a short time both products were being sold concurrently.
47RC Papers, Y Silk surface and N Smooth Lustre
All these papers could be handled under a Kodak Wratten safelight with a 25watt bulb, fitted with a 10H filter, (Dark Amber), for as long as 4minutes of direct lighting provided the paper was kept at least 4feet from the safelight.
The papers could be exposed by Tri-color (additive filtration) exposures, or by White light (subtractive filtration) exposure. The labels on the boxes and packets carried exposure factors for both types of printing methods, used when changing from one batch of paper to another. The exposure factors were no help when making the initial set-up exposure, using the papers for the first time. First time use required a trial and error procedure, but once a successful print was obtained, the exposure factors on subsequent packets could be used to modifty the result achieved with the first pack of paper.
The early instruction sheets for Ektacolor Commercial paper and Ektacolor 20 paper suggested exposing a first test print with no printing filters in the light beam. But as the papers were balanced for the use of yellow and magenta filters to correct the negative's colour balance (cyan filtration was hardly ever needed), Kodak, in their later instruction sheets, advised a starting filtration of 50 Yellow and 50 Magenta filters. (50 50 --). Either Kodak Colour Compensating ( CC ), or Kodak Colour Printing ( CP ), filters could be used to correct the color balance, but Colour Printing filters could not be placed in the image forming beam below the lens, as definition of the print would be reduced. Colour Compensating filters, being thinner, could be placed below (or above) the lens, but Colour Printing filters had to be placed in the filter drawer of the enlarger (above the negative and the lens). Any number of Colour Printing filters could be put in the filter draw, but no more than three Colour Compensating filters could be fitted below the enlarger lens if maximum definition was of importance. By the early 1960s, most colour processing laboratories were making colour prints using enlargers fitted with Agfacolor or Chromega colour heads, a much quicker way of changing the filtration than the laborious method of handling separate gelatine filters.
It was recommended that the enlarger should be fitted with a heat absorbing glass, or filter, to remove any infra red light to which the paper was sensitive. The filter, or heat absorbing glass, was fitted directly above the printing filter drawer to protect the filters from the heat of the lamp.
If it was found that the majority of the test prints exposed exhibited a green cast, and yellow/cyan filtration was needed to correct the colour balance despite the heat absorbing glass placed above the filter draw, Kodak recommended the CPIR filter to be fixed above or below the enlarger lens. This filter would bring the colour balance of most test prints to a red/magenta direction, and colour casts could be corrected using the more normal yellow/magenta filters. The CPIR was an infra red absorbing filter. All Ektacolor papers were sensitive to infra red light to some extent.
For white light printing, a Ultra Violet filter was recommended. This was a Wratten No. 2B or a CP2B. It could be placed in the filter draw and left there permanently. For Tri-colour printing it was not necessary, as each of the three Tri-colour filters filtered out UV light.
Earlier Kodak colour negative printing papers, such as Kodak Ektacolor Commercial paper, could be processed satisfactorily in a combined Bleach-Fix bath, and it is possible that Agfa patents had prevented Kodak from using a Bleach-Fix bath in their earlier colour print processes. (For formulae of Bleach-Fix baths compatible with Kodak colour papers, see the technical sections of the British Journal of Photography Annuals for 1968 and 1970.)
In the U.S.A., in 1971, this paper was marketed as Kodak Ektacolor 30RC paper, designed to be processed in the then, new, Ektaprint 3 process. Ektacolor 30RC was only obtainable in roll form, and was mainly made available to photofinishers. Roll widths varied from 3½ inches wide to 11 inches wide, with roll lengths of 250 feet to 700 feet. The only surface available was Glossy, a highly glazed surface. Manufacture of 30RC was discontinued in 1974, replaced by Ektacolor 37RC paper.
Kodak Ektacolor 37RC paper was made available in roll and sheet formats. It had, like 30RC, a resin coated base which made for fast processing and drying in Ektaprint 3 chemicals. The paper was available in three surfaces:- Glossy, Code F; Silk, Code Y; and Smooth Lustre, Code N. The sheet sizes, in the U.S.A., ranged from 8 inches by 10 inches to 30 inches by 40 inches and roll sizes from 2¾ inches width to 40 inches width. The larger width rolls were for mural prints and came in 50 foot lengths. The narrow rolls were for photofinishers and were packed in 250 foot and 500 foot lengths. When air dried, the Glossy paper produced a highly glazed surface and the other two surfaces were much the same as the black and white papers equivalent surfaces.
Ektacolor 37RC paper was approximately the same speed as Ektacolor Commercial paper, and could be handled under a Kodak safelight filter No.10H for about 4 minutes provided the paper was kept at least 4 feet from the safelight.
The paper could be exposed using either Tri-color filters, or by the White Light method. The U.K. instruction sheet dated October 1971 recommended a trial starting filter pack of 50 Yellow and 50 Magenta, made up of Kodak colour printing filters or Kodak colour compensating filters. This was exactly the same filter recommendation as given in the later instruction sheets and Data sheet PP-12 for Ektacolor Commercial paper.
The labels on the boxes carried factors and filter changes for both Tri-colour and White light printing when changing over from one batch of paper to another. It was possible that the factors and filter changes may have worked satisfactorily when changing from one type of paper to another, e.g. from Ektacolor Commercial/Professional/47RC to Ektacolor 37RC paper.
The UK instruction sheet also has a very useful section on mounting prints, as at that time few photographers, including the author, had experience in mounting colour prints made on paper with a resin coated base. Before the introduction of Ektacolor 37 RC paper, the author, when trying to dry mount some prints made on Kodak Ektachrome RC paper, ruined several good prints made on this material during a Trial and Error session of mounting colour prints for his College portfolio!!
Ektacolor 37RC paper was suitable for making prints from all Kodak colour negative films. A Data release sheet, No. E-69, dated January 1973, gives suggested trial starting filtrations for Kodak Vericolor Type S, Ektacolor Professional Type S, Kodacolor X, and Kodacolor II films for three different types of enlarger or commercial printer light sources. Kodacolor X negatives were given a lower yellow filtration, i.e. less yellow, than Vericolor/Ektacolor Professional films because the mask used in the film was slightly more yellow. Kodacolor II filtrations were higher, because the negatives were slightly more blue in colour. In 1974, Kodak Vericolor Professional films were introduced, and because of their slightly blue/magenta mask, trial filtrations were similar to Kodacolor II films.
Ektacolor 37RC paper could also be exposed by the Tri-color method of printing, one exposure through each of three filters, such as:- No.70 Red, or No.25 Red, No.99 Green and No.98 Deep Blue. Varying the exposure through the filters changed the colour balance and density.
The paper was available in sheets and rolls, and could be handled in the darkroom by direct safelighting, under a Kodak safelight filter No.13 for no longer than 1½ minutes at a distance of at least 4feet from the safelight. By 1976, the older Kodak safelight filters, Nos.10 and 10H, were no longer recommended for Ektacolor papers, but the filters remained on the market for use with Kodak Ektacolor Print and Slide films, and for Kodak Panalure papers, panchromatic black and white papers, used for making b&w prints from colour negatives.
Filter factors were given on the sealing label for Tri-color and White Light printing to assist the printer when changing from one batch of paper to another.
74RC paper was available in three surfaces; F, Glossy, N, Smooth Lustre, and the then new E surface, termed as Lustre Luxe. Lustre Luxe was gradually replacing the previous Y, Silk surface, which had been first available as Ektacolor 20 RC paper Y in 1968 in the USA. The new surface was recommended for portrait and social photography. The surface was similar to, but not identical to, the Kodak Bromide and Bromesko black and white papers' White Fine Lustre surface at that time, until their demise in 1982.
Kodak Ektacolor 74RC paper was replaced by Ektacolor 78 Paper in 1979 but 74RC was reinstated in 1982 (see the following section).
Research using Eastman Kodak
literature shows the following chronology:
In 1980: Some Kodak instruction sheets in the UK advised that Ektacolor 78 paper could be handled under a No.13 safelight filter for slightly longer than 3 minutes before the print exposure took place, but no longer than 3 minutes after exposure.
In 1982: Early in 1982, both in the UK and US, the 78 papers were increased in speed and renamed Ektacolor 78 paper Type 2492. In the US, the still available 74RC paper became Ektacolor 74RC paper Type 2492. Later in 1982, Ektacolor 78 paper Type 2492 was further increased in speed and was renamed Ektacolor 78 paper Type 2524.
In the US, Ektacolor 74RC paper Type 2492 was increased in speed and became Ektacolor 74RC paper Type 2524. This paper was then also introduced into the UK in just an E (Lustre-Luxe) surface and only a narrow range of sheet and roll sizes. 74RC was a lower contrast alternative to Ektacolor 78 paper and was designed for social, wedding, and portrait photography.
Because of the speed increase of these Type 2524 papers, their allowed exposure time under a safelight was reduced. Some instruction sheets stated just 1 minute, but others suggested the papers were safe to be handled for 1 minute before the print exposure took place, but no longer than 1 minute after exposure.
Plus and Ektacolor Professional Papers
This new Ektacolor Professional paper was a totally different material to the previous Ektacolor Professional paper mentioned above for processing in the P-122 process.
All Ektacolor Professional paper was manufactured in the USA and only the E Lustre-Luxe surface was imported and sold in the UK, where it was available in limited sheet and roll sizes.
This box contains F Glossy surface and was sold in the USA hence the price ticket of $42.85
This box dates from the mid to late 1980s.
In 1989: Kodak's RA-4 sheet papers first appeared.
Follow the link to read about the transition from the previous EP-2 to the new RA-4 process and materials and to read a user experience.
P-122 Seven-Bath Processing Procedure, from 1942
Total Time: 42 minutes
As far as is known, the processing procedure outlined above was used without change for Kodacolor paper from 1942 to 1955.
Higher Temperature Seven-Bath Processing Procedure, from 1959
A Kodak UK Professional Catalogue for July 1963 shows that Kodak were still selling the Seven-Bath P-122 chemicals for Ektacolor paper as late as July 1963, a year after Agfa had changed to their faster Four-Bath system.
Although general indication is given in each of the following sections of the years when processing procedures, or number of baths involved, changed, the table below should be consulted for definitive information regarding what & when changes took place in the USA and UK chronology.
|P-122 Six-Bath procedure, from 1962 in the US
The faster high temperature procedure paved the way for a Six-Bath P-122 process (not including the wash steps) in 1962 (but see also Note 5 below), development being at 85°F (other solutions at 85°F or 75°F), with a further reduction of the total wet processing time. This sequence is taken from the Kodak Color Dataguide of 1964. This process was mainly for Ektacolor Professional Paper.
The Six-Bath process combined the Hardening Fixer and the Hardener to become Formalin Fixer. Also, by this time, a hardening agent had been added to the First Fix. The actual Eastman Kodak 7-page instruction booklet gives Step 3 as First Fixing Bath. The booklet is dated December 1962.
As far as Michael Talbert knows, the 28 minute and the 23 minute procedures were not widely used in the UK.
The P-122 Process was renamed Ektaprint C in 1965 with minor chemical changes; the Buffer becoming Stabilizer. Processing times were identical to the Five-Bath P-122 process above.
In 1965 the collective name of the Kodak colour negative paper print processing chemicals was changed to Ektaprint C. The times and temperatures of the processing baths and washes remained the same except the last bath, the Buffer bath, was changed to a Stabilizer bath.
The Ektaprint C processing chemicals were used for dish processing, batch processing in tanks, or in continuous processing machines designed to process long rolls of paper. The chemicals were available in sizes from 1 litre to 100 litres. Kits of chemicals in 1 litre and 5 litres were obtainable, the developer being separately packed in Unit 1, and the Stop-Fix, Bleach, Formalin-Fix, and Stabilizer were packed in Unit 2. The processing chemicals were also sold separately to make 3 gallons, 40 litres, and 100 litres of working solution. All sizes were sold as concentrates to be mixed to make the working solution.
C Processing Procedure
A tin of Kodak Ektaprint C Bleach chemicals
The tin contained two powder components to be diluted in water to make 3 Gallons of working solution of Bleach chemicals. This was not part of a Kit of chemicals. Each working solution of the processing chemicals for the Ektaprint C process were available separately in 3 Gallons, 40 litre, and 100 litre sizes.
The 3 Gallon size was intended for colour printing laboratories batch processing prints through a 3 gallon tank line using Kodak Colour Print processing baskets. Once mixed, the Bleach chemicals would last for 8 weeks, unused or partially used, in a 3 gallon tank. On a commercial scale, most tank processing lines were replenished, and the processing solutions were not replaced unless dirt had worked its way into the system or one or several solutions were badly contaminated. The process could be monitored by processing Ektaprint C Control Strips on a regular basis.
This tin dates from 1965. Kodak included a 4 page instruction sheet packed with the 3 Gallon Ektaprint C Developer chemicals.
with Ektaprint C chemicals
Five dishes were essential, keeping one special dish for the colour developer to prevent contamination. A Paterson Dishwarmer with a thermostat was used to maintain the developer temperature within the strict limits of 85° +/ ½°F. Processing was always carried out using the higher 83° 87° sequence, doubling the Bleach time for Commercial paper. Since the prints were of rather soft contrast when developing at the Kodak advised time of 6 minutes, the development time was increased to 8 minutes at 85°F for all prints made on Ektacolor Commercial paper.
The last wash, step 7, was also increased in time to about 6 minutes, for greater permanence. All washes were carried out in a large sink with running water at approximately 85F.
Test strips were processed only up to the Bleach stage, then washed briefly and dried for assessment. As Commercial and 20 papers exhibited a blue/magenta colour cast whilst wet, it was extremely difficult to judge colour casts before drying. Hence, a small, amateur print dryer was used to dry the test strips and so reduce the time before assessment could be carried out.
The Paterson dishwarmer performed well, but could accommodate only two 8 inch by 10 inch dishes on the top. Michael kept the Developer and Bleach dishes on the warmer, and the Stop-Fix dish was placed by the side of the warmer. The Stop-Fix temperature was at room temperature for processing, but in winter the solution had to be warmed occasionally to prevent its temperature from falling below about 65°F. This seemed to work well, and no detrimental effects were noticed in the processed prints caused by using the solution at a lower than recommended temperature.
The Developer dish was covered with a wooden lid to prevent oxidation and also prevent other solutions from being splashed into the dish whilst transferring prints from the wash to the Bleach. When a final print was made, the Formalin Fixer and Stabilizer bottles were heated to 87°F and the solutions poured into the two extra dishes. Most prints made were 8 inch by 10 inch or smaller, but 15 inch by 12 inch prints were tried, pouring the solutions in and out of one large dish.
There was little processing latitude with regard to the Developer temperature, but more latitude with timing errors.
Both makes of paper did not keep well and so off-white borders were common. Ektacolor 20 paper was of very soft contrast and had a semi-gloss surface which enhanced the low contrast. Both papers were fibre based, so drying times were long.
In date Ektacolor Commercial paper was capable of giving very good results, as long as the original negative was not too soft, or the subject matter was of low contrast. Michael seldom made prints on Ektacolor 20 paper. The two packets that he tried were out of date and gave very soft results with poor whites and muted colours.
Compared with using a light
tight drum for print processing, dish processing was difficult
By 1972, Ektacolor 37 RC paper was available for processing in the then new Ektaprint 3 chemicals, giving a much shorter total wet processing time of 8 minutes.
In 1963, Eastman Kodak introduced two compact colour print processing machines, each designed to process one sheet of paper in the amazingly short total processing time of 7 minutes at a high temperature of 100°F (37.8°C). The smaller machine was known as Model H11-L and was capable of processing prints up to 11 x 14ins. It required 125ccs of each processing solution for each processing run. The larger machine was known as the Model 16-K; mainly for professional photographers, it took sheets of paper up to 16 x 20ins. It required 250ccs of each solution for each processing run. The machines were known as Drum Processors and used the same colour processing chemicals as the (then) dish and tank processors, i.e. Five-Bath Process P-122, or later, Ektaprint C. Because of the high operating temperature, the individual chemical baths had different formulations than the dish and tank process. The collective name for the process was CP-5. The same process timings were used with both drum processors.
The machines consisted of a hollow drum on its side, into which water was pumped from a large dish of temperature controlled water at 100°F. The water flowed in and out the drum keeping the surface temperature of the drum at 100°F. The drum, powered by a small electric motor, revolved through a trough which held the processing chemicals. At the end of each processing step the trough was lowered and the chemical drained out, then the trough was raised and another chemical bath was poured into it. The stainless steel surface of the drum was covered in grooves, or channels, which picked up the chemical solution at the bottom of the drum and carried it underneath the print surface. The print was held emulsion down on top of the drum underneath an epoxy coated net blanket, attached to a metal bar which clipped into slots at the front of the processor.
The 16-K processor had its own water heating unit built into it on the left hand side. For the smaller H11-L machine it was possible to purchase a separate heating unit that provided continuous temperature controlled water to the Processor. This unit was made by TECHNE of Cambridge. The unit was called the Techne 2 and it clipped onto the inside of a fairly deep dish of water. A hose from the Techne 2 was put inside the processing drum and water at the correct temperature for maintaining 100°F was pumped continuously into the drum, with the water subsequently draining back into the deep dish. The hose also served for washing the back of the print.
Picture alongside taken from the Kodak book Printing Color Slides, page 18, publication No.E-96.
The original Kodak instruction sheet for the CP 5 process, dated December 1964, tells how to load the drums.
To start, you poured the developer into the tray at the base of the drum, then switched on the drive motor. The drum then revolved taking the developer over the top of the drum in the grooves. Then the room lights were switched off leaving the Wratten 10H safelight on, and the print or test strip, which had been put in a light tight box after exposure, was placed in a dish of water when using the 16K processor, or the reservoir for the Techne 2 heating unit when using the H-11L processor.
After ½ minute the print/test strip was taken out of the dish or reservoir, drained for 10 seconds, and then arranged on the net blanket which was also soaked in the dish or reservoir. A metal bar was fixed at the end of one of the shorter sides of the net blanket. The short side of the print or test strip was placed at the bar end of the blanket, spaced about ½ inch away from the bar with the emulsion facing the operator, the back of the print against the blanket.
The print was then laid emulsion down on top of the drum with the net blanket on top of the print and the operatror rapidly hooked the metal bar, at one end of the net blanket, into a lug either side of the drum. As soon as the print touched the drum, you started timing the development. Loading the drum with a print or test strip took 3 or 4 seconds, in the dark or by the very dim light of the Kodak Wratten 10H safelamp ! You had to have a chemical solution (or wash water) between the drum and the print, or the 'drag' of the dry drum surface would eject the print off the drum. Hence the developer had to be in the trough at the base of the drum before the print was loaded. The internally heated rotating drum then heated the developer to the right temperature before the print was placed onto the drum and developed.
After the development step, the temperature of the drum most likely dropped slightly, but this didn't matter much as the temperature wasn't critical for the other solutions or washes, and the drum quickly regained its 100°F temperature.
In 1963, when the drums were first sold in America, it was an amazing process, less than 8 minutes to process a print. Some labs in the U.K. at that time were still using process P-122 at 42 minutes to process a print. The P-122 short process, later Ektaprint C, almost halved that time by 1965. By 1966, Agfa Gevaert had almost halved their Short Process, the Pa process, to a total of 17 minutes by raising the process temperature to 77°F.
The developer temperature had to be at 100°F +/ ½ a degree F. The rest of the solutions and washes could deviate 2°F either way from 100°F.
Below are pictures of a box
of Ektacolor Commercial paper dating from 1964 to 1966. Ektacolor
Commercial paper was only manufactured in the UK.
The P-122 process on the label refers to the five bath P-122 process described prior to the CP-5 process. Ektacolor Commercial paper could also be processed in CP-5 chemicals for drum processing, or in the later Ektaprint C chemicals. This label was printed before the P-122 process name was changed to Ektaprint C (in the U.K.), but the instructions packed inside the box gave details of the CP-5 process. (Printing date of instructions is October 1964.)
The Kodak Colour Print Drier, Model 1-R, was able to dry a print in seven minutes, and it was capable of drying a print up to 20 x 16ins. The dryer was recommended by Kodak for use with either Rapid processor.
In 1963, Kodak Ektacolor Professional Paper was used with the drums as this had sufficient emulsion hardness for the high processing temperature. This paper was available mainly in the U.S.A, but by 1964 the drums were beginning to be sold in the U.K., and in that year a new colour printing paper was marketed, namely,Kodak Ektacolor Commercial Paper. Only made in the U.K., this paper was suitable for use with the rapid processing drums. It had a fairly high contrast, with brighter whites, and was particulary suitable for advertising photography. It could also be processed with P-122 chemicals and the Ektaprint C process.
In 1963, 7 minutes was a remarkably short total processing time. In 1963, Agfacolor and Gevacolor papers took ½hour to process. But by 1971, a colour print processed in the new Ektaprint 3 chemicals took only 8 minutes, with the advantage of using only three solutions and one wash step. By the mid-1970's, drum processors were beginning to be used more for the convenience of processing one print at a time rather than speed of processing. Also, by then, it was found much easier to load a print inside a light-tight drum, with the chemical solutions being poured inside the drum. This enabled the whole processing procedure to be conveniently carried out in white light. Such processors were the Wilkinson and later the Simmard Color Drum and the Kodak Printank. (For the amateur home processing market, noteably Durst, Jobo and Paterson produced versions of varying sophistication and price).
Michael Talbert had considerable experience of processing prints using the H11-L drum in the early 1970's. His comments are:
By the mid-1960's, another larger colour print processor was available for processing prints from 20 x 16ins to 30 x 40ins. The Kodak Color Processor Model 30 could process a single sheet of 30 x 40ins paper in 7 minutes using CP 100 chemicals. The processor could be operated in ordinary room lighting as the exposed print was placed inside the drum. There were 10 processing steps of ½minute each, excepting the development time of 2½ minutes.
In 1971, the Kodak Ektaprint 3 process replaced Kodak Ektaprint C, CP-5, and CP-100 processes. Ektaprint 3 consisted of three chemical baths and one wash for fast processing of Ektacolor 30RC and 37RC papers. Colour printing papers of the byrata base type, i.e. non-RC, such as Ektacolor Commercial, Professional, and earlier resin coated papers, Ektacolor 20RC and 47RC, could not be processed in Ektaprint 3.
Ektaprint 3 Process for dish, and batch processing in 3 gallon tanks using colour print baskets.
With regard to dish processing, because the print went from the Developer into the Bleach-Fix without a wash in between, rapid contamination of the Bleach-Fix bath was common by too much developer being carried over into the Bleach-Fix. Kodak recommended a Drain Time of at least 15 seconds over the developer dish or tank, but despite this, contamination of the Bleach-Fix still produced cyan or magenta stains on the prints in many instances. To alleviate this problem, an extra bath and wash could be inserted into the processing sequence.
37 RC Paper Processing in Ektaprint 3 using the Kodak Rapid Colour
Processors, H-11L and 16K
As the back of the resin coated paper was much smoother than the paper base support of Ektacolor Commercial paper, a green coated 'Net Blanket' was used to hold the resin coated paper on the drum. The green blanket gripped the smooth surface of the back of the print to prevent it from sliding out of the drum.
Note by the author: It has to be said that I processed many test strips and prints on Ektachrome RC paper between January 1971 and April 1971 using the regular Net Blanket on a Kodak H-11L drum processor and as far as I can remember I never had any problems of prints or test strips sliding out of the drum. So perhaps it may not have made much difference which Net Blanket was used for R.C. paper processing. I am certain that the new green Net Blanket was not on the market in early 1971. The thickness of both papers was the same or very nearly so.
A different colour developer was used for drum processing Ektacolor 37RC paper. Kodak Ektaprint 300 Developer was made specially for use with the drums mentioned and for the larger Kodak Rapid Processors Models 30 and 30A. The Bleach Fix and Stabilizer were the same chemicals as used for dish, tank, and continuous processors. In the U.K. in 1973, Ektaprint 300 Developer was available in a 1 U.S. gallon size, (3.8 litres.). At the same time in the U.S, Ektaprint 300 Developer was available in 1 U.S. gallon and 3½ U.S. gallon sizes.
The smallest packing of Ektaprint 3 Bleach Fix or Stabilizer was 5 litres. (From Kodak Professional Catalogue, November 1973). The smallest size of Bleach Fix or Stabilizer sold in the U.S. was 1 U.S. gallon. (Kodak Professional Products Catalog, 1973 74).
37 RC Paper Processing in Ektaprint 3 using the Kodak Rapid Colour
Processors, Models 30 and 30A
Safelight Filters for Colour Negative Printing Papers
Kodak safelight filter No. 13 was recommended for use with all Ektacolor papers, to be used in a safelamp with a 15 watt bulb. The previous 10, or 10H, filter could still be used with a 7½ watt bulb.
All Ektacolor papers could be handled for a little over 3 minutes at a distance from the safelight of no less than 4 feet before exposure, and no longer than 3 minutes after exposure with either safelight filter. The No. 13 safelight filter gave a brighter illumination than the 10H or 10. The colour of the No. 13 safe light filter was designated as Amber, best described as an orange brown. The 10H or 10 was approximately the same colour but darker, designated Dark Amber.
Kodak Ektaprint 2 chemicals for processing Ektacolor papers were introduced in 1976. The process was essentially a shortened version of the Ektaprint 3 colour print process with the Stabilizer bath omitted. Temperatures of the solutions and washes were slightly different to Ektaprint 3.
By increasing the final wash time from 2 minutes to 3½ minutes it was possible to omit the Stabilizer giving the same degree of permanence to the prints. It was also recommended to increase the development temperature to 91°F, (33°C), giving a development time of 3½ minutes.
Two additional steps, Stop Bath and Wash, could be inserted when the developer carry over into the Bleach Fix was excessive, causing marks and stains on the prints, see below These additional steps were almost essential for dish processing.
37RC and Ektacolor 74RC papers in the Kodak Rapid Processors
using Ektaprint 300 developer and Ektaprint 2 Bleach Fix
By 1984 Ektaprint 300 Developer became Ektaprint 200 Developer and was now advised for use in small Tube Processors as well as the Kodak Rapid processors.
In the late 1970s, the first table top roller transport machines had been put on the market, such as the Agfaprint machines, and Ektaprint 200 Developer was recommended for these machines if using Ektaprint 2 chemistry. Ektaprint 200 Developer was obtainable in 5 Litres and 15 litres sizes.
Ektaprint 300 Developer was for use with Ektaprint 2 or Ektaprint 3 Bleach Fix. There was never an Ektaprint 300 or 200 Bleach Fix.
The only change in the Kodak
Rapid Processor sequence (see above, here
and here) was the time in the
last wash which was extended to 1 minute, the Stabilizer bath
|Ektaprint 2 colour print processing chemicals for processing machines ~ 1980|
By 1980 Kodak Limited (U.K)
were manufacturing Ektaprint 2 colour print processing chemicals
for many different processing applications and types of processing
1. Rapid Colour
2. Small volume
Rotary Discard Processors.
3. Replenished Tank Lines.
4. Continuous Strand Processors.
A paper dryer was incorporated at the end of the machine. Once the end of the paper had been through the dryer the operator unclipped the rod, tore the end of the paper off the rod, and attached the end of the paper to an empty spool. The spool would revolve taking up the processed prints until the end of the roll had been reached. A small darkroom had to be built at the loading end of the machine as the paper rolls had to be loaded onto the machine in total darkness. In use, the machine's electric motor was running continuously, as then the operator could load one roll while others were still going through the processor. As the author found out in 1975, you had to learn how to load the machine while the machine was running, and in the dark !
This was the system with the Durst 1112 colour print processor. This machine would take rolls of paper up to 12 inches wide. It was not possible to process sheets of paper on this machine. The two solutions and one wash were temperature controlled, and the replenishment system was automatic. The Durst 1112 Processor could be used for Ektacolor papers with Ektaprint 2 or 3 solutions, or with Agfacolor papers using Process 85 or 86. Process 85 and 86 were three solution chemistries plus one wash, similar to Kodak Ektaprint 3. It was an excellent colour print processor and took up little floor space. Dry to dry processing times were about 10 to 15 minutes.
5. Roller Transport Processors.
The Kreonite roller transport processor was a well known make. Others included the Hostert Automata, and various models of paper processors by San Marco taking different paper widths. There were many other makes of roller transport processors, some taking paper widths up to 54 inches wide for mural prints. In the 1970s, Kodak Ektacolor papers and Agfacolor papers were made in widths up to 50 inches wide.
Quantities of Ektaprint 2 chemicals ranged from a small kit of chemicals to make 1 litre of Developer and Bleach Fix for amateur photographers using dishes or rotary discard tanks to 100 litre units of each solution for continuous strand and roller transport processors, plus others, in use in medium to large colour processing laboratories. Ektaprint 3 Stabilizer chemicals were also obtainable to make up to 100 litres of working solution.
Eastman Kodak published various
documents on the handling, processing and printing of their colour
negative materials. One of the first of many was a 16 page booklet
issued free of charge to professional photographers entitled
Printing Color Negatives on Kodak Color Print Material,
Type C, published in 1956. This was later enlarged to an
A5, 56 page publication entitled Printing Color Negatives,
the first edition being published in July 1958. Printing Color
Negatives gave instructions on how to make successful prints
using the then, new, Kodak Color Printing Filters which could
be placed in a filter draw above the negative (white light printing).
The book was subsequently enlarged again to A4 size, published as the fourth edition in 1969. By this time the Ektaprint C process had been in use for a number of years, to be replaced by Ektaprint 3 in 1970. A fifth edition, published in May 1975, gives instructions on Ektaprint 3 chemistry, and printing Ektacolor and Vericolor II negatives on Ektacolor 37RC paper.
|Michael Talbert sends his many thanks to Richard Frieders of the Photographic Society of America (P.S.A) for finding and sending various articles from past P.S.A. Journals concerning Kodacolor film and other information relating to colour negative materials.|
Michael Talbert started making colour prints in 1969, using Kodak Ektacolor Commercial paper. He was a photographic colour printer in the 1970s, printing colour negatives mainly onto Agfacolor paper. He also had experience using about 10 types of Kodak paper, plus other makes, Gevacolor, Fuji, Paterson, Konica.
Michael now sets up and takes Retro fashion pictures, but prints them digitally.
P-122 Seven-Bath Processing Procedure, from 1942
Total Time: 42 minutes
As far as is known, the processing procedure outlined above was used without change for Kodacolor paper from 1942 to 1955.
P-122 Seven-Bath Processing Procedure, from 1959
A Kodak UK Professional Catalogue for July 1963 shows that Kodak were still selling the Seven-Bath P-122 chemicals for Ektacolor paper as late as July 1963, a year after Agfa had changed to their faster Four-Bath system.
Six-Bath procedure, from 1962