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  1. #1
    Stephen Frizza's Avatar
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    Kodak Direct Positive Developer

    is anyone able to give me information on a kodak developer called Kodak Direct positive developer. I have never used this and know nothing about it. I would love to know what its properties were.

    many thanks

    ~Steve
    The Lighthouse

  2. #2

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    this is a KIT for the reversal processing of certain B & W negative films.
    First Developer, Bleach, Clearing Bath, re-exposure,Second Developer, Fix.

  3. #3

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    There are a number of things that may have been called "Direct Positive developer." The most likely are the developers used for reversal processing of black and white film. Kodak once made a film called "Direct Positive" in 35 mm and 828 sizes. It produced black and white slides when reversal processed in a kit Kodak sold. The developer in that kit was D-88:

    Kodak D-88 developer for reversal processing
    Water (52C) 750 ml
    Sodium sulfite (anh) 45 g
    Hydroquinone 22.5 g
    Boric acid (xtal) 5.5 g
    Potassium bromide 2.5 g
    Sodium hydroxide 22.5 g
    WTM 1 l
    Use full strength. Develop Direct Positive Paper 45 seconds at 20C, rinse, bleach for 30 seconds in R-9, rinse, clear in CB-1, rinse, re-expose, redevlop in T-19 or D-88, wash, and dry.

    This developer was used for both Direct Positive film and the corresponding Direct Positive paper, which was frequently used as the "film" in photo booths.

    Later, after Direct Positive film was discontinued, Kodak manufactured a reversal processing kit that would make slides from TMax 100 film by reversal processing. I'm not sure what developer they used in the kit, but a separate instruction sheet told the photographer to use D-94, the black and white reversal first developer used for motion pictures:

    Kodak D-94 reversal film first developer
    Water (50C) 750 ml
    Metol 600 mg
    Sodium sulfite (anh) 50 g
    Hydroquinone 20 g
    Potassium bromide 8 g
    or
    Sodium bromide 7 g
    Sodium thiocyanate (51%) 9.1 ml
    Sodium hydroxide 20 g
    WTM 1 l
    pH at 27C = 12.75
    Specific gravity at 27C = 1.074
    Develop motion picture reversal film for 2 minutes at 20C or 40 seconds at 35C.

    I don't remember if either kit used a special second developer, but the normal motion picture reversal processing instructions call for D-95 as the second developer:

    Kodak D-95 reversal film second developer
    Water (50C) 750 ml
    Metol 1 g
    Sodium sulfite (anh) 50 g
    Hydroquinone 20 g
    Potassium bromide 5 g
    or
    Sodium bromide 4.5 g
    Potassium iodide 250 mg
    Sodium hydroxide 15 g
    WTM 1 l
    pH at 27C = 12.15
    Specific gravity at 27C = 1.065
    After an 800 footcandle second reexposure, develop reversal film for 50 seconds st 20C or 20 seconds at 35C.

  4. #4

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    It was a rapid process developer for Kodak Fine Grain Positive Release film. The film was used for high speed contact printing of the movies for release to the theatre. Do you have the developer? Or, do you need to find some? To my knowledge, it hasn't been produced in quite a few years. If you need some, use Dektol 1:2 for 3 minutes.

  5. #5
    Photo Engineer's Avatar
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    If this is the product I remember, the film was a direct positive emulsion and the developer was a normal developer. But, IDK if the reversal agent was in the emulsion or the developer. If it was in the developer, then Dektol will not work. If it was in the emulsion, any good non-solvent developer will work.

    PE

  6. #6

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    direct positive developer

    Hello Steven:Kodak used to make a direct positive processing kit in the late 60's or early 70's that allowed users to expose panatomix-x film at asa 80 and process the film with this kit to produce b&w slides.Kodak Pub. G-9 has all the info for this process including the formulas to make the solutions from scratch.
    The first developer was called D-67,which was for all intents D-19 with 3ml. of Sodium Thiocyanate(51% solution) added. The fogging developer was called FD-70a and consisted of parts "A" and "B".Part "A" consisted of Sodium Dithionite (A flammable solid) and Part "B" consisted of a solution containing Kodalk Balanced Alkali and 2-Thiobarbituric Acid.This developer had to be mixed just before use because it only lasted 1 to 2 hours after mixing.The Bleach Bath was called R-9 and consisted of sulphuric acid(Conc.) and Potassium Dichromate.The clearing Bath was called CB-1 and consisted of a Sodium Sulphite solution.A plain stop bath made from 28& Acetic Acid was used and the fixer was Kodak Formula F-5.

    I hope this answers all your questions.

    Doug(aka spoolman)

  7. #7
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    One must distinguish a direct positive film from a direct positive or reversal process.

    In the case of a direct positive film, the emulsion gives a positive image by the process of Developing, stop or wash, fix and wash. A special emulsion is used to give a positive image by a negative process. Sometimes a special developer must be used. Any developer must be low in solvents.

    In the case of a direct positive process or reversal process, a positive image can be obtained from most any B&W film by the process of Developing, stop or wash, bleaching the negative silver image, clearing, washing, fogging, developing, wash or stop, and final fix followed by a wash.

    Doug describes the use of a reversal process which can be used with most any B&W film.

    BTW, the wikipedia reference lists sodieum dithionite as flammable, but the Merck index does not. There are conflicting reports. It decomposes in water to sodium bisulfite and sodium bisulfate making the solution acidic. It is a reducing (fogging) agent. However, this same name is applied to several chemicals, and this chemical may be found listed under several alternative names to make things very confusing.

    My Kodak Direct Positive kit is #175-3052.

    PE

  8. #8

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    Quote Originally Posted by Photo Engineer View Post
    One must distinguish a direct positive film from a direct positive or reversal process.

    In the case of a direct positive film, the emulsion gives a positive image by the process of Developing, stop or wash, fix and wash. A special emulsion is used to give a positive image by a negative process. Sometimes a special developer must be used. Any developer must be low in solvents.

    In the case of a direct positive process or reversal process, a positive image can be obtained from most any B&W film by the process of Developing, stop or wash, bleaching the negative silver image, clearing, washing, fogging, developing, wash or stop, and final fix followed by a wash.

    Doug describes the use of a reversal process which can be used with most any B&W film.

    BTW, the wikipedia reference lists sodieum dithionite as flammable, but the Merck index does not. There are conflicting reports. It decomposes in water to sodium bisulfite and sodium bisulfate making the solution acidic. It is a reducing (fogging) agent. However, this same name is applied to several chemicals, and this chemical may be found listed under several alternative names to make things very confusing.

    My Kodak Direct Positive kit is #175-3052.

    PE
    I find the light fogging works equally well on most emulsions.
    The trick, when using the permanganate based bleach, is mix it at half the usually recommended strenght so to lessen the softening action it can pose on the emulsion. Works quite well.

  9. #9
    RoBBo's Avatar
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    I'm trying to dig up more on this.
    Are there currently any available direct positive films? (Positive from normal 'negative' processing?)

    Has anyone used any of these processes for current films?
    I'm considering trying to make some 11x14 slides and I'd rather not use DR5.
    Any ideas for the logistics of re-exposing?
    Any kits that don't require re-exposing?
    Help?

  10. #10

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    I have a box of Kodak SO-132 8x10 direct positive film...

    I tested it once...and...yup...with normal processing I got a positive image

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