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Thread: PCTEA anyone?

  1. #11
    gainer's Avatar
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    I never claimed anything magic, just a sulfite free developer concentrate that lasts a long time in storage.

    My revised advice about mixing included a covering of microwave-proof plastic wrap with edges sealed but loose enough so that the first signs of vapor pressure higher than atmospheric could be observed. That temperature is more than enough, and gives time to remove the source of heat before any contact between the atmosphere and combustible vapor can occur.

    Heating over an open flame or electric heating element is best done with low heat and a candy thermometer in the liquid. 150-200 F is hot enough. In fact, the precautions that are prescribed for making sugar syrup or taffy should be safe enough.
    Gadget Gainer

  2. #12

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    PC TEA

    When I last mixed up PC TEA I used the water bath method. I poured the TEA into a stainless steel cup and then placed the cup into an aluminum pan. I then poured boiling water into the pan and waited a few minutes to start stirring the TEA. The acsorbic acid should be added first to prevent oxidation of the phenidone. After the ascorbic acid is dissolved I add the phenidone. At the temperature I was working, the phenidone did not fully dissolve. I poured the mixture into a bottle and the rest of the phenidone dissolved on standing.

  3. #13
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    Thanks for all the advice everyone. Holding the TEA at 175F while adding first the ascorbic acid then the phenidone with constant stirring on a magnetic stirrer seems to have done the trick as far as mixing the developer goes. I'll be trying it out on HP5+ over the weekend.

    Ash

  4. #14
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    I wonder your reasons are for trying a developer that requires so much effort (and hazard) to even have it mixed properly. There are so many developers out there that come pre-packaged. Why PC TEA?

  5. #15
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    Quote Originally Posted by aparat View Post
    I wonder your reasons are for trying a developer that requires so much effort (and hazard) to even have it mixed properly. There are so many developers out there that come pre-packaged. Why PC TEA?
    The idea of a developer with D-76 like characteristics but a very long shelf life is appealing. Patrick's description of extremely fine grain with HP5+ (my favorite 400 speed film) was also interesting. It turned out that at the lower temperature, 175F, it wasn't so dangerous to try and the immediate availability in my darkroom of both ascorbic acid and phenidone made it worth trying. In fact, it seems less dangerous to make than a Rodinal type developer.

    Regards.

    Ash

  6. #16
    CBG
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    Quote Originally Posted by aparat View Post
    I wonder your reasons are for trying a developer that requires so much effort (and hazard) to even have it mixed properly .... Why PC TEA?
    Effort? Two components and a solvent. Stir and store. As simple to make as D-23 and arguably easier to use. The concentrated liquid stock means it can be measured out for use as a liquid. Very convenient to dose out with a child's medicine syringe.

  7. #17

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    There's not much effort in making PC-TEA, and once you've made a batch up (I usually make 1 litre at a time), it keeps in concentrate form for ages. Plus it's cheap, and the ingredients are relatively easy to get hold of, and relatively safe.

    I make mine using Patrick's formula, but I mix the phenidone in a little methylated spirits (alcohol), and the vitamin C powder in a little warm water. Then I gently heat the TEA in a glass jug in the microwave until the jug feels about as hot as a hot cup of tea. Then I stir in the phenidone, when that has all been mixed in, I gradually stir in the vitamin C. I reheat it as necessary (to hot tea stage) and continue mixing until everything is mixed in. Then I bottle it into 250ml dark brown glass jars, let it cool down till it is warm, then cap it and cellar it!

    It is a nice developer that seems to give the better qualities of Rodinal along with the better qualities of Xtol.

  8. #18

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    Quote Originally Posted by Photo Engineer View Post
    Keith;

    I don't use PCTEA. I have my own formulas. In addition to which I don't believe in magic bullets for solving problems. Good old D-76 and HC-110 work well for me, or one of my own specialty formuolas if I want something special - but not magic.

    PE
    Ron, I never considered PC-TEA as a magical-miracle brew, but more as a Phenidone + Ascorbate variant of the Kodak HC-110 type. I believe that HC-110 also contains ethanolamines. I also use D-76 as my standard developer.

  9. #19
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    Keith;

    Good point in the underline. But my point, that you missed, was that if a formula exists, it exists to solve a problem. In this case it exists to reducing mixing hassle and keeping of concentrates. Does it do that in a safe, economical, reliable fashion and still give high quality results? IDK, the results are not in yet.

    I have seen reams of data showing the effects of D-76 and HC110 along with other film developers, along with picture data. I have seen a lot of things related to commercial products, but the entire story on PCTEA is not out there, just parts of it. So, there is no "magic", just feelings of comfort with it. Thats about it.

    I tend to believe that it is good for quality, but without proof, I cannot say for sure. I am concerned about people mixing it up in their kitchen in a microwave to the temperature of a "cup of tea". So, I am fence sitting until I see a reason for using it that is compelling.

    As I said, I can mix up similar formulas that take no heating.

    PE

  10. #20

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    A hot water bath is probably the safest way to heat triethanolamine in a non-lab environment.

    That said, working solutions of PC-TEA can just as easily be made by adding the constituent components directly to water in the right proportions -- 20 ml of triethanolamine, 1.8 g of ascorbic acid, and 0.05 g of phenidone in one litre of water (best to pre-dissolve the phenidone in a little alcohol). You lose the advantage of having a single-solution, very long-lasting developer, but no heating is required.

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