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  1. #11
    gainer's Avatar
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    I just finished mixing and testing a sodium version of Rodinal. 50 grams of p-aminophenol.HCl, 130 grams of sodium bisulfite, 70 grams of sodium hydroxide in the form of Red Devil lye from the supermarket. You need not concern yourself with the mysterious few undissolved crystals. Just mix those ingredients in enough water to make a liter of stock solution. I tested it on Arista II 100 at both 1+25 and 1+50 dilutions using the times listed on the side of a bottle of AGFA Rodinal, and the results were just as I remembered them.
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  2. #12
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    The times I used were those listed for APX 100.
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  3. #13

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    re: The dangers of potassium hydroxide and sodium hydroxide

    Quote Originally Posted by outofoptions
    Since they sell lye at the local grocery store, I wouldn't be all that concerned. ALL of the formulas I have seen published tell you how to safely handle it. Yes, there is always stern warnings to make sure you respect the potential, but don't let that put you off.
    The safety of mixing your own developers is, of course, relative. Something like PC-Glycol is pretty low on the danger scale; just restrain yourself from eating or drinking the ingredients or rubbing them into open wounds and you should be fine. Potassium hydroxide and sodium hydroxide, though, are potentially dangerous if mishandled; they can cause warm water to boil, perhaps spewing chemicals all over the place, and if you get them on bare skin (or worse, in your eyes), they can damage your own tissues. Pyro developers are also potentially risky to mix, but for different reasons. Of course, none of these things is as dangerous as, say, mixing up your own TNT. I expect the average person could mix up Rodinal with little risk of personal injury if that person reads the instructions carefully and takes appropriate safety precautions, such as using cold water for mixing the hydroxide and wearing protective gear (safety goggles, gloves resistant to hydroxide, etc.). Nonetheless, the safety issues do bear mentioning because Rodinal creation is high on the danger scale, at least as calibrated for darkroom chemistry.

  4. #14
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    Here is yet another variation. Sodium salts, p-aminophenol, sodium sulfite, sodium hydroxide.

    To about 750 ml of water at room temperature, add
    p-aminophenol...............38 grams
    sodium sulfite (anh)........160 grams
    sodium hydroxide............23 grams
    Add water to make 1 liter.

    There is no danger of the this mixture boiling when the hydroxide is added, although it's a good idea not to add it very rapidly. (Never add water to hydroxide. That is when you will get localized boiling and spattering. If you should foolishly decide to add water to hydroxide, then is the time to do it so rapidly that it has no time to react.)

    Using the base p-aminophenol instead of the hydrochloride and the sulfite instead of the bisulfite reduces the amount of hydroxide and eliminates the chloride that results in the "original" formula. My resulting solution was clear with a slight yellow tint. There is again no need in mixing to worry about leaving an undetermined few crystals undissolved.

    Arista II 100 at 1+50 required only 8 minutes at 70 F. The reduced time over the previous version may have been due to the fresher agent or to a miscalculation of the amount of hydroxide. Either way, I like it. A 12X enlargement at normal viewing distance shows no graininess and all the other characteristics that have kept Rodinal in use for 125 years.

    Notice that a liter of working solution at the 1+50 dilution has 0.76 grams of p-aminophenol, 3.2 grams of sodium sulfite and 0.46 grams of sodium hydroxide. If there were no sulfite, the pH would be about 12. I don't have a pH meter, so cannot tell the actual value. It certainly qualifies as a classical compensating acutance developer. More important to me is that looking at my negatives and prints convinces me that it is what theory says it should be. Now all I have to do is to wait 10 years to see if it will have the staying power of good old Rodinal. That will give me an excuse to live to 88 years of age.
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  5. #15
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    Rodinal is a well-know formulation, and others apart agfa do sell it.

    Check those:

    Adox APH09
    Calbe R09
    Fomadon R09

  6. #16
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    True enough, but the availability of a fully equivalent and easily made home brew will help keep the price from running away. The ingredients are too widely used to become scarce, I believe. The one thing that might spoil our fun is to have p-aminophenol declared a controlled substance. Well, I forgot the other thing. What if there were no film that could be developed in Rodinal?
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  7. #17

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    I have no idea how to substitute Rodinal...the R09 is the old formula, and afaik nothing is a true substitute for the current real deal (new recipe Agfa stuff). I have stocked up a bit and will do for approx. the next 5-8 years now, and after that I will see what will be available for souping at that time.

    Morten

  8. #18
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    Quote Originally Posted by modafoto
    I have no idea how to substitute Rodinal...the R09 is the old formula, and afaik nothing is a true substitute for the current real deal (new recipe Agfa stuff). I have stocked up a bit and will do for approx. the next 5-8 years now, and after that I will see what will be available for souping at that time.

    Morten
    I just told you how. It contains the same ingredients, looks the same, smells the same, works the same as the last AGFA Rodinal I bought. If you are averse to using sodium salts, mix 18 grams of p-aminophenol, 92 grams of potassium sulfite and 16 grams of potassium hydroxide in 400 ml of water at room temperature and add water to make 500 ml. Compare it with the Rodinal you bought. Remember the formula if Rodinal becomes unavailable or exorbitantly priced.

    p-aminophenol has too many other commercial uses to become unavailable. Has anyone tried to concoct a developer out of Tylenol? Maybe a combination of Tylenol and Folgers instant will be the soup of the future. If nothing else, it should cure the common headache.
    Gadget Gainer

  9. #19

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    According to Elie Shneour of Agfa this is the original formula for both Rodinal
    and Calbe R09. The formula was the 9th in the Agfa recipe book (Rezeptbuch 09) hence the name.

    Rodinal and Calbe R09, as now formulated, contain potassium hydroxide. In
    addition, Rodinal now contains potassium bromide. When Rodinal was first formulated the metabisulfite and hydroxide were available as concentrated solutions making manufacture very simple.

    Solution 1

    Distilled water ......................... 625 ml
    Paraminophenol HCl ...................... 100.0 g
    Potassium metabisulfite ................. 300.0 g

    Add a pinch of the bisulfite to the water and then add the p-aminophenol hydrochloride and when dissolved add the rest of the metabisulfite.

    Solution 2

    Distilled water (10°C) .................. 300 ml
    Sodium hydroxide ........................ 200 g
    Distilled water to make (10°C) .......... 400 ml

    Method of Preparation

    Concentrated paraminophenol formulas are prepared differently from other
    developers. Follow the directions below carefully.

    Add 280 ml of Solution 2 to Solution 1 with stirring. A precipitate of paramino-
    phenol will form. Slowly add more Solution 2 with constant stirring until there
    is a sudden darkening in color. At this point, begin adding Solution 2 drop by
    drop until all but a small amount of the precipitate dissolves.

    IT IS IMPORTANT THAT NOT ALL OF THE PRECIPITATE DISSOLVES.

    Should all of the precipitate dissolve then add a few crystals of potassium
    metabisulfite to restore a small amount of precipitate.

    Make up the resulting solution to 1 liter. Decant the solution into a stoppered
    bottle and allow to stand overnight. Then filter the solution and place in well
    stoppered bottles of 2 to 4 ounce capacity.

    Paraminophenol is sufficiently acidic to form a salt with potassium or sodium
    hydroxide. This salt is quite stable in the absence of any excess hydroxide.
    It is extremely important that a small amount of precipitate remain as this
    guarantees that an excess amount of hydroxide has not been added. If all the precipitate dissolves then the solution will not keep.

  10. #20

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    I think pat may have mis calculated the amount of hydroxide. Calculations show that your formula has 0.348 moles of paraaminophenol and 0.575 moles of sodium hydroxide. From my understanding you are to add enough hydroxide to convert the phenol into the phenolate ion. You have about 9 grams extra hydroxide which will make the pH quite high. That may explain your shorter times.

    Jurgen

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