Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,502   Posts: 1,543,387   Online: 790
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,264
    Images
    148

    Toning by Colour Development

    TONING BY COLOUR DEVELOPMENT


    This method gives by far the greatest colour range to be easily obtained on paper prints. By using four readily available colour couplers in various combinations, together with a common colour developer,- almost any colour image can be obtained, and can be readily repeated if the solutions are carefully prepared. It is a means of obtaining particularly rich warm blacks and browns.


    Solutions Required


    Colour Developer.


    (i)
    Sodium metabisulphite 5 gm
    p-diethylaminoaniline sulphate 10 gm
    Water, to 00 cc


    (ia)
    Genochrome or Activol 11 gm
    Water, to 100 cc


    (ii)
    Calgon 2 gm
    Sodium carbonate (anhyd.) 17 gm
    Sodium formaldehyde sulphoxylate 5 gm
    Potassium bromide 1 gm
    Water, to 1000 cc


    Coupler Solutions


    Magenta: p-nitrobenzyl cyanide 0-5 gm
    Alcohol 100 cc
    Yellow : Acetoacet-2:5-dichloranilide 2 gm
    Alcohol 100 cc
    Blue-green: 2:4-dichloro-1-naphthol 1 gm
    Alcohol 100 cc
    Blue: 1-Naphthol 1 gm
    Alcohol 100 cc


    These stock solutions will keep reasonably well in brown bottles if filled to the neck and well corked, but the working solution must be mixed immediately before use as it is unstable. The working solution is prepared by mixing three parts of Developer (i) or (ia) with 100 parts of Developer (ii) and then adding ten parts of Coupler solution. Suitable mixtures of coupler for a complete spectral range are:


    Crimson
    Magenta 8
    Yellow 2


    Scarlet
    Magenta 5
    Yellow 5


    Orange
    Magenta 2
    Yellow 8


    Yellow
    Stock solution


    Green
    Yellow 5
    Blue-green 5


    Blue
    Stock Solution
    or
    Blue-green 8
    Magenta 2


    Violet
    Blue-green 5
    Magenta 5


    Purple
    Blue-green 5
    Magenta 8


    (The blue image obtained with the mixed couplers is not as bright as the image obtained from the blue coupler, but can be used if the number of solutions is to be kept to the minimum.)


    Fixing Bath.
    Hypo 200 gm
    Water, to 1000 cc


    First Bleach.
    Potassium ferricyanide 50 gm
    Potassium bromide 20 gm
    Water, to 1000 cc


    Second Bleach.
    First bleach 30 cc
    First Bath 70 cc


    The fixing and first bleach baths will keep well, but the second bleach has a life of only a few minutes, and must therefore be mixed just before use.


    Processing Procedure
    Direct development of the latent image in the colour developer is possible, but the more reliable method is to develop the latent image in a normal print developer, fix and wash, and convert the silver image to silver bromide, fog it, and then colour develop. The colour developer produces a light silver image in addition to the dye image and this can either be left in to give a rich 'tinted' image, or it may be removed to leave the bright dye image. The following time-table is suggested:


    First Developer 2 minutes 20°C
    Stop Bath 1 minute 20°C
    Fix 10 minutes 20°C
    Wash 30 minutes
    First Bleach ---------
    Wash 5 minutes
    Fog 1 minute 1 ft from 100W lamp
    Colour Developer 5 minutes 20°C


    If the silver image is to remain:


    Wash 5 minutes
    Fix (in fixing bath given) 5 minutes
    Wash 20 minutes


    or if the dye image only is required:


    Wash 20 minutes
    Second Bleach -------
    Wash 20 minutes




    Notes on Processing


    1. The first development should be full, but fog must be avoided. If necessary, extra bromide or an antifoggant should be added to clear the highlights.


    2. The first fixer must be fresh or colour stains will be produced.


    3. Bleaching times are not given as these will depend on the condition of the solutions and the print density. Both first and second bleach stages should be long enough to completely remove the black silver deposit.


    4. Continuous and vigorous agitation during colour development is essential. or the shadows will be of low density and will have no gradation.


    5. Washing times given may need alteration, depending on the weight of the paper base and on the efficiency of the washing system. Too little washing between first fix and first bleach will destroy the light densities, and too little before or after colour development will produce stained highlights. If in doubt, wash longer. The dyes produced by colour development are sensitive to acids, and acid solutions after colour development should be avoided. Also, like the majority of dyes, they may fade on exposure to strong sunlight for long periods.


    From the British Journal of Photography Annual 1965, first published in an earlier Almanac in the 1930's.
    It's an easy process and works very well.

    Ian

  2. #2

    Join Date
    Jun 2012
    Location
    UK
    Shooter
    Multi Format
    Posts
    1,388
    Thank you very much Ian.
    Any ideas where folk might obtain the couplers these days?
    I've drawn a blank so far ...

  3. #3
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,264
    Images
    148
    I got my colour couplers through Scientific & Chemical Supplies in Wolverhampton but they probably got them Koch-Light, I had an account with both companies.

    This page may be of interest,
    I'll add the details from it (I supplied all the information) I scanned and generated the PDF file.

    Ian

  4. #4
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,264
    Images
    148


    This 1949 Johnsons Colourform booklet
    was tucked into one of my BJP Almanacs when I bought it and gives an idea of how the method works. (It's too large to upload here 4.7mb).

    Ian

  5. #5

    Join Date
    Feb 2010
    Location
    Montreal, Canada
    Shooter
    Multi Format
    Posts
    4,721
    Very interesting, Ian. Thanks for posting this.

  6. #6
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,264
    Images
    148
    Quote Originally Posted by Michael R 1974 View Post
    Very interesting, Ian. Thanks for posting this.
    Try having a look at Bob Carlos Clarkes images particularly the book/exhibition Dark Summer, he used an arsenal of toning techniques including dye couplers. He most likely used the Tetenal colour coupler kit, his work was printed on Agfa paper, they sponsored him and used his images for their advertising.

    Ian

  7. #7
    Rudeofus's Avatar
    Join Date
    Aug 2009
    Shooter
    Medium Format
    Posts
    1,641
    Images
    10
    I looked for these couplers on Sigma Aldrich's web page, and their price varies a lot: 68 Euros for 100g of magenta coupler (CAS 555-21-5), 65.5 Euros per 25 milligrams of yellow (CAS 2044-72-6), and over 200 Euros for 25 grams of blue-green (CAS 2050-76-2). Can you confirm that these are the compounds called for, and if that is indeed the case, what you paid for yellow?

    Also, do you have any info on how long term stable these dyes are?
    Trying to be the best of whatever I am, even if what I am is no good.

  8. #8
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,264
    Images
    148
    It's around 25 years possibly longer, since I last bought colour couplers so I've no idea now what I paid for them. There are/were alternative couplers particularly for yellow, somewhere (in storage) I have my notes from when I was doing the research into toners with the alternatives listed. It's worth checking the colour couplers used in Kodachrome processing as these would have been made in larger quantities, prices for older couplers may be high as there's almost no demand/production.

    You'd need to cross-check the MSDS or other data-sheets to check the alternative names for these compounds.

    Stability of any colour coupled dye is partially dependent on storage and exposure to light but a dye-coupler toned print should last as well as a colour print under similar conditions.

    Ian

  9. #9
    Jim Taylor's Avatar
    Join Date
    Nov 2009
    Location
    West Yorkshire, UK
    Shooter
    Multi Format
    Posts
    138
    Wow!

    This is just the thing I've been looking to get my teeth into!
    Now, to find the couplers....

    1. Raid every dark, musty store cupboard at work!
    2. Hope for the best!
    Cheers,

    Jim.

  10. #10

    Join Date
    Aug 2012
    Shooter
    35mm
    Posts
    109
    Principles of Color Photography, Evans, Hanson, Brewer, edition 1953 on page 261 lists the following dye couplers as suitable for Kodachrome:


    cyan
    2,4-dichloro-1-naphthol


    magenta
    p-nitrobenzyl-cyanide


    yellow
    naphthoylacetanilide


    Text talks of p-phenylenediamine developers.

    Friedman's "The History of Color Photography" has a good discussion concerning the effect of substituting couplers or developers. See Chapter 23, Color Coupling Development.

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin