Polaroid P/N clearing bath

Discussion in 'Large Format' started by dan_craig|1, Nov 5, 2002.

  1. Most of the formulas I have seen for mixing the sodium sulfite
    bath to clear Polaroid 55/665 negatives require weighing out the
    powdered chemical in grams. Having no scale to make these
    measurements, does anyone have a formula with measures
    that dont require one? Thanks in advance.
     
  2. It's been awhile since I've mixed any up, but I think you just take a pound of sodium sulfite and mix it to make 64 o.z. of working solution for type 55. The 665 negs require a different concentration though...me, I just mix a capful of permawash for a small tray of water & use that.....hope this helps.
     
  3. I don't know how much sodium sulfite you are starting with, but if you have a pound of it, it is 453.59 grams. Polaroid I believe says to mix 440 grams to 2 liters of 70 degree water. It is not that exacting. A pound to 2 quarts will work fine.
     
  4. Dan, I recently purchased a 1 pound container of sodium sulfite from Artcraft and dissolved the entire contents in 2 liters of distilled water. Close enough to an 18% solution. I used a Rubbermaid 2 liter bottle from Wal Mart to mix and store. This sodium sulfite solution can be re-used many times over. A handy measurement to remember is that a level teaspoon of anhydrous sodium sulfite weighs 7.6 grams, according to Steve Anchell.
     
  5. i also just use water. takes a bit longer but they are always clear by the time i get home.
     
  6. I use Permawash, 3 oz to one gallon of water. It works fine. And it elinates measyrement and dissolving dry chemistry.
    Bob
     
  7. Greetings,
    I do use permawash as studio-clearing bath, and then I simply immerse the negative in a bath of Heico NH-5 hardener only (0.5 oz in 24 oz of plain water). Would it be necessary to add the fixer to the hardener's solution?
    Thank you.
     
  8. Albertini, Polaroid warns not to use fixer with Type 55 negatives, under any circumstances. Heico Permawash contains ammonium sulfite, as well as sodium sulfite. I wonder if Permawash is suitable for clearing the Type 55 negatives? Can any chemists out here give an opinion?
     
  9. Albertini, Polaroid warns not to use fixer with Type 55 negatives, under any circumstances. Heico Permawash contains ammonium sulfite, as well as sodium sulfite. I don't think it is an 18% sulfite concentration. I wonder if Permawash is suitable for clearing the Type 55 negatives? Can any chemists out here give an opinion?
     
  10. eugene-

    i have been using kodak's hypo clearing agent which is sodium
    sulfite and another chemical, possibly ammonium sulfite. i have
    been working under the assumption that the second chemical is
    basicaly either a preservative or an accelerator for the sodium
    sulfite. either way, it doesn't seem to affect the negatives
    aversely.

    however, if someone wants to refute that, i would be happy to
    make changes so my negs aren't any less archival.

    and speaking of which, could someone give me an idea of how
    archival a t55 neg is? will it last as long as a normal b&w 4x5
    neg?

    -m
     
  11. what is Permawash? I don't particlarly like sodium sulphite, its a pain to dissolve properly without leaving small grains in the solution.
     
  12. permawash is Heica proprietary name for hypo-clearing agent. sodium sulfite is the active ingredient. it is sold in liquid form so dissolving the crystals is not an issue. however, a plain water bath works fine. as with any other halide medium, the permawash simply speeds up the fixer clearing; it is not essential to that task. i have type 55 negs that are many years old that were simply cleared in water.
     
  13. Thanks for all the great input. I hope it keeps coming!

    I'll throw another item into the mix now: What sort of final rinse/wetting agent works best with this film? LFN? PhotoFlo? Something else? Or nothing at all?
     
  14. Dan, after treatment in the 18% sodium sulfite solution, until the negatives look clean and clear, I wash them for about 15 minutes in running water. Then, I fill an 8X10 tray with approx. 1 liter of DISTILLED water. Two, or three drops of Kodak Photo Flo, LFN, Ilfotol, or similar wetting agent are added to the tray of DISTILLED water. Soak the film in the tray of wetting agent solution for a few minutes, drain, and hang to dry in a dust-free area. Dried negatives are stored in Mylar sleeves. They seem to be as archival as my conventionally-developed negatives, but I only have twenty years of experience with them.
     
  15. From the Polaroid website (regarding fixer/hardener with Type 55 P/N negatives):

    To prevent scratches: Negative scratch resistance can be improved by treating the processed negative (after clearing in water and sodium sulfite) in a solution of Kodak Rapid Fix with Hardener (parts A & B) for two minutes. This solution should be made up and used in accordance with Kodak's recommended mix procedures, chemical caution statements, wash times and temperatures.
     
  16. I have used SPRINT fixer remover, undiluted, to clear and "hold"
    type 55 negs. They are in Patucket, R.I. and sell all liquid black
    and white photo chemistry.
     
  17. when I wash type 55 in sodium sulphite I notice that a very fine, black film floats off after a couple of seconds, which doesn't happen with straight water. I assumed this is what the sodium sulphite is for?
     
  18. The negative is to be treated within 5 minutes.
    This step hardens and removes residual chemicals of the process. This step also renders soluble the anti-halation dye.

    18% Sodium Sulfite solution

    Sodium Sulfite 6 ounces (180 grams)
    Water 32 ounces (1 liter )
    Store solution in brown bottle at full strength.
    Place negative in this solution and agitate - developer layer will drop off however gentle rubbing with cotton wad or sponge will assist.
    Rinse the negative in running water 30 seconds to 5 minutes depending on the degree of chemical removal dictated by your archrival requirements. Follow with wetting agent such as Kodak Photo-Flow. Allow to air dry.

    If sodium sulfite is not available, the negative can be washed in pain water 60 F (15.5 C). Anti-halation dye will be annoying and absence of a hardener makes film easily damaged. But plain water will be OK with gentle rubbing to remove regent layer.

    Regent is alkaline and may cause reddening of skin if contact is prolonged - wash hands after contact.
     
    Last edited: Jun 2, 2020
    bengtfredén likes this.
  19. Maybe chemical scales were expensive back in 2002 when this thread was posted? But in these drug-crazy times you can pick up very accurate electronic scales for not much money at all.

    Just ask your local drug-dealer where they bought theirs.

    You can also make sodium sulphite in solution by mixing the right proportion of sodium metabisulphite (food/wine preservative) and caustic soda.
     

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