|Early Kodacolor & Ektacolor print material - researched by Michael Talbert|
to this web page:
Michael Talbert has provided a considerable amount of historical information on the early Kodak print films, Kodacolor, Ektacolor and Vericolor, plus their printing processes. This is set out below.
To assist in reaching a specific topic, please use the hyperlinks in the following index.
Also, see his research on Ektachrome transparency slide film and prints on Ektachrome RC paper.
Also, see his research on early Agfa colour print materials.
Kamerman has recently
(February 2012) sent me some pictures of items within his amazing
collection of early Kodak films. Charlie says "I
have hundreds of boxes of film from 1891 through the 1980's."
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.
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.
Film in 1955 ~ Process C-22
Subsequent Process C-22 KODACOLOR Films
Kodacolor X remained on the market until 1975, when replaced by the new Kodacolor II films which were first introduced in 1972 for Kodak Pocket Instamatic cameras, taking the new 110 size cartridge. Processing was done in Kodak Flexicolor chemicals, later known as Process C-41. By 1975, roll film, 35mm, and cartridge format type film were all available as Kodacolor II (100ASA; later joined by Kodacolor 400 in 35mm from 1977 and roll film from 1978 - UK dates). The C-22 Kodacolor & Kodacolor X films were gone forever.
The C-22 process did live on,
however, for another four years after the demise of C-22 Kodacolor
X in 1975.
The C-22 process was last mentioned in the British Journal of Photography Annual (BJPA) 1985 edition, with formulae and processing steps.
C-22 Unit 1 part kit
The Stop-Bath component was one bottle of liquid chemical to be diluted with water. This would keep for 8 weeks, unused or partially used.
The Unit 2 part contained the Hardener, Bleach, Fixer, and Photo-Flo chemicals for the rest of the process.
This Unit 1 Kit dates from 1972, when the author was processing a considerable amount of Kodacolor X and Ektacolor films.
Listed in the Kodak Professional Catalogue for the U.K. in 1964 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. 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
Kodak Ektacolor Internegative Films 6110 and 6008 (35mm) were processed in Kodak Colour Film Process C-22 but the normal C-22 developer was replaced by a special internegative developer. The rest of the solutions for processing the film were the same C-22 solutions, washes and timings as for camera colour negative films. Many laboratories in the U.K. operated a separate 3 gallon tank processing line specifically for Ektacolor Internegative sheet film.
The Internegative Developer working solution was made up of Internegative Replenisher to which was added Internegative Starting Solution. Using a 3 gallon tank line the development time was five minutes for the sheet film and six minutes for the 35mm film at 75°F +/ ½°F with an increased agitation rate. The Internegative Replenisher was used on its own to replenish the Internegative developer.
Michael Talbert has experience of developing Internegative sheet film in the normal C-22 developer for 7 minutes at 75°F. Internegatives processed in normal C-22 developer did not match the quality of Internegatives processed in the special Internegative developer. Less shadow detail was recorded on the negative and increasing the exposure did not help matters as the Internegatives then had too much contrast. The contrast of Ektacolor Internegative film was controlled by the exposure, less exposure less contrast, increasing the exposure increased the contrast. The exposure range of the film was about four stops, keeping within the limits of 1second to 16seconds (though this was increased to seven stops in the 1970s, 1/10second to 16seconds). If the exposure time was decreased below 1second, or increased much above 16seconds, the highlight to shadow colour balance changed and prints made from such Internegatives would show colour mis-matches e.g: Pink (magenta) highlights green shadows. Within limits, the colour balance and contrast of the Internegative film could be adjusted so that an improved print could be made from an otherwise out of balance, underexposed transparency, but it was difficult to make an improved print from an over exposed transparency, though still possible to alter the highlight to shadow colour balance fairly successfully. A starting filtration was given in the instruction sheet for Ektacolor Internegative film of 50 yellow, 20 magenta, 0 cyan. (50 20 -) made up of Kodak Colour Printing filters. This filtration could be changed to correct the highlight to shadow colour. When making the print it was not possible to alter the highlight to shadow colour balance with the print filtration.
Slight contrast changes could be made to the print by altering the development time but this sometimes resulted in cross curves, highlights of the print turning the opposite colour to the shadow areas, especially with lower contrast. Agfacolor papers generally had more latitude in contrast changes by altering development times that Kodak Ektacolor papers. When making a print from an internegative, it was far better to alter the contrast of the print by changing the internegative exposure than varying the development time of the printing paper.
Michael's own experience of making many Internegatives and then making prints from these Internegatives, was that the film could give outstanding results provided filtration (controlling the highlight to shadow balance was carefully set up) and exposure were correct. For prints made from 35mm or 2¼" square original transparencies, it was best to first make an enlarged internegative, 4 x 5ins being the normal size.
10 x 8ins Internegatives made from 35mm transparencies were not uncommon if a horizontal enlarger, e.g. a De Vere Mark X, was used to make a print measured in feet. Generally, the larger the required print, the larger the Internegative.
The Vericolor films were only
intended for laboratory use & processing, not for exposure
in a camera.
The internegative films were for making negatives from transparencies which could then be printed onto Ektacolor paper. Kodak Vericolor Print Film was designed for making large display transparencies from colour negatives and internegatives. It had a thick base and a matt surface to facilitate retouching and was available in sheets and wide rolls. It replaced Kodak Ektacolor Print Film.
Kodak Vericolor Slide Film was designed for making 35mm and 46mm transparencies from colour negatives and internegatives. The film had a thin, clear base and was available only in rolls, 35mm and 46mm wide. It replaced Kodak Ektacolor Slide Film. Vericolor Slide Film was initially available as SO-372. An SO numbered product meant that it could be withdrawn at any time without warning and there was no guarantee that a similar product would replace it. 5072 was most likely an improved version of SO-372.
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)
Film Processing after 1955 ~ (Process
type of Kodacolor Film - see above)
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.
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 !
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.
and White Prints
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.
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.
Color Print Material Type C (see above, under Kodacolor paper)
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 U.K. 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 with 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 U.S.A. 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 U.S.A. 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.
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. I have 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) I try to show how there may have been three distinct methods.
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 around 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 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 around 20 years.
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.
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 U.S. 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 U.S.A. who wanted to handle the processing and printing of Kodacolor film.
Color Print Material, Type C
It is not known if a safelight was used for the first three steps when processing Kodacolor paper, but by the mid-1950s, a safelight was available which had been designed specially for Kodak Ektacolor Paper, namely, Wratten Series 10. It was a dark amber colour, and the (then) new Ektacolor paper could be handled in the direct light of the safelight for a limited time, about 4 minutes.
The P-122 Colour Developer used Kodak colour developing agent CD-2, but this developing agent was changed to CD-3 in 1955.
The Hardener chemicals contained Formaldehyde as the hardening agent, to provide extra hardening after the Harden-Fixer. The Buffer was a kind of Stabiliser. Prints not treated in the Buffer would show stained whites, (border areas) and eventually, blue stains would appear on the backs of prints.
Rolls of prints were dried after the Buffer treatment without rinsing, the drying drums giving off acid fumes.
It is unlikely that the prints were glazed, as this would have incurred additional time in the Hardener.
As far as I know, the processing procedure outlined above was used without change for Kodacolor paper from 1942 to 1955.
P-122 Processing Procedure from 1959
Six-bath procedure from 1962
As far as I know the 28 minute and the 24 minute procedures were not widely used in the U.K. The seven-bath 42 minute procedure being replaced by the 22 minute procedure as late as 1963.
The last P-122 procedure was renamed Ektaprint C in 1964 (U.S.A.), 1965 (U.K.), with minor chemical changes, and the Buffer becoming Stabiliser. Processing times were unchanged.
The first type of Ektacolor paper was marketed in 1958. Various improved versions followed and it was still listed for sale in three sizes in the Kodak Dealer Catalogue for 1966 to 1967. It was replaced by Ektacolor 20 paper in 1966.
Ektacolor 20 RC paper was replaced by Ektacolor 30 RC paper in 1971 although, at this time, both products were being sold concurrently.
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 could be processed in the 5 bath P-122 chemicals, Ektaprint C chemicals, and in the rapid colour processors. Professional, a fibre based product, was introduced as long ago as 1961, and was recommended for social, wedding , and portrait photography. It was said to exhibit the highest degree of image stability of all the Kodak colour papers. 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
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.
In the U.S.A., from 1964, 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. In the U.K., this change took place a year later.
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.
Michael Talbert had experience of processing Ektacolor Commercial and Ektacolor 20 papers in dishes, like black and white prints, using Ektaprint C chemicals, during 1969 to 1971.
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. 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 puirchase 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 first three steps had to be carried out under a Kodak Wratten 10H safelight, but before this stage, the drum was switched on and the developer was poured into the trough. Then, under the safelight, the exposed print was taken from its light-tight box and was pre-soaked for ½ minute in the large dish containing the Techne 2 before being loaded onto the drum. After ½ minute, it was taken out of the dish, positioned on the net blanket, and drained for 10 seconds. Holding the print on place on the blanket, the blanket and print were lowered onto the revolving surface of the drum and when the emulsion surface made contact, the net-blanket bar was quickly clipped to the front of the drum. Timing of the development step began as soon as the emulsion of the print made contact with the drum.
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.
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.
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.
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.
See his web page selling Retro Greeting Cards