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  1. #21
    gainer's Avatar
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    Quote Originally Posted by Flotsam
    I have no clue what effect using the formula with the misplaced decimal point would have on the film. I'm strictly a recipe follower. I only mentioned it because when I became interested in your formula, I just searched on the name and found it on APUG. Without a basic knowledge of photo chemistry, I would have followed the formula unquestioningly to the letter even if it had mistakenly called for a cup of Chicken broth . I just thought that correcting the the formula in the might help avoid confusion among recipe followers like myself.
    You need not defend yourself for your sugestion of editing. It gave me a good chance to see what would happen. I did the test first with the recipe as it should have been, on HP5+ 35 mm, as per my usual ploy of exposing a whole roll to the same scene. In this case it was a step density wedge. Then I added enough phenidone in glycol to bring the total to 10 times the original amount and repeated development of a strip from the same roll.

    I was unable to identify one strip from the other either visually or by scanning and displaying them side by side. When I am fully awake I will make a side by side contact print.

    Some of you will be surprised, I'm sure, that 10 times the amount of phenidone made no significant difference in the negatives. As long as you keep the ascorbic acid constant and the phenidone at least a fortieth of that amount, there will be neither advantage nor disadvantage to increasing the phenidone.
    Gadget Gainer

  2. #22
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    I mixed up some PC-TEA following directions I got from somewhere in this forum awhile ago. I heated it to 250 and while everything mixed up OK, it turned a very dark brown in color (like black coffee almost) and smells horrible, even now when I dilute it for developing. It works perfectly well as announced, and gives me good negs, but about drives me out of the darkroom with the odor.

    Is this characteristic? If so, I'll go back to my TEA-less existence. Is it the result of over-heating (I notice that Gainer's post mentions heating it to 160 degrees.)? Not only is the smell bad, but it persists in the darkroom for a day or more.

    Larry

  3. #23
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    I guess I created a monster. A long dead one at that. I think it does not stink so badly when it is made at the lower temoerature. I know it is not nearly so dark. That color is due to the fact that TEA darkens with heating.

    You might like it better as an A-B stock with the A being same as PC-TEA but using propylene glycol as the solvent. You may then use TEA as the B or you may use the B part of PMK or you may experiment with various amounts of sodium carbonate. Nicholas Twist uses a teaspoon each of sodium carbonate and sodium bicarbonate to the liter.

    In either TEA or glycol the life of the A solution is very long.
    Gadget Gainer

  4. #24

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    Quote Originally Posted by gainer

    Some of you will be surprised, I'm sure, that 10 times the amount of phenidone made no significant difference in the negatives. As long as you keep the ascorbic acid constant and the phenidone at least a fortieth of that amount, there will be neither advantage nor disadvantage to increasing the phenidone.
    Yup, I'm surprised. This weekend I tried a PC-TEA version with 8 times the recommended amount of phenidone on Delta 400, and it reduced activity by 30%. That surprised me too. I'm guessing it has to do with the reaction products of phenidone inhibiting development.

  5. #25
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    I did make the contact sheet comparing the two phenidone concentrations side by each, and the biggest difference I could make out was a slight increase in base fog with the increased phenidone. What else was in your developer?
    Gadget Gainer

  6. #26

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    Quote Originally Posted by gainer
    I guess I created a monster. A long dead one at that. I think it does not stink so badly when it is made at the lower temoerature. I know it is not nearly so dark. That color is due to the fact that TEA darkens with heating.

    You might like it better as an A-B stock with the A being same as PC-TEA but using propylene glycol as the solvent. You may then use TEA as the B or you may use the B part of PMK or you may experiment with various amounts of sodium carbonate. Nicholas Twist uses a teaspoon each of sodium carbonate and sodium bicarbonate to the liter.

    In either TEA or glycol the life of the A solution is very long.
    I have not experienced recently any strong discoloration of either -TEA or glycol solutions. What I try to do is mix things that go into solution with difficulty (bromide, metabisulfite, etc.) at a very high temperature, say 250 F or higher, then allow the temperature of the solution to drop to about 160F to 170F before adding the reducers (phenidione, pyrocatechin, pyrogallol, etc.). Ascorbic acid can be mixed at a very high temperature without any discoloring, but it mixes just as easily at about 170F so I usually wait for the solution to cool before adding it as well.

    Sandy

  7. #27

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    Quote Originally Posted by gainer
    What else was in your developer?
    It was fake PC-TEA, mixed on the spot from powdered AA, pure TEA and phenidone in rubbing alchohol. Do you think the alchohol could be to blame? At the regular phenidone/AA ration, I used 1.25 ml of alcohol to 250 ml of working solution. At 1:10 ration, it was 5 ml.

    Which brings me to another point: I didn't use 8 times as much phenidone, but 4 times as much. Sorry!

  8. #28
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    Quote Originally Posted by Maine-iac
    I mixed up some PC-TEA following directions I got from somewhere in this forum awhile ago. I heated it to 250 and while everything mixed up OK, it turned a very dark brown in color (like black coffee almost) and smells horrible, even now when I dilute it for developing. It works perfectly well as announced, and gives me good negs, but about drives me out of the darkroom with the odor.

    Is this characteristic? If so, I'll go back to my TEA-less existence. Is it the result of over-heating (I notice that Gainer's post mentions heating it to 160 degrees.)? Not only is the smell bad, but it persists in the darkroom for a day or more.

    Larry
    I mixed up the DS-14 listed in the formula section - heated the TEA up to 250 and added all the Ascorbic acid and the Phenidone and it turned a pale yellow and has no smell at all. Humph ...

  9. #29

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    Quote Originally Posted by fhovie
    I mixed up the DS-14 listed in the formula section - heated the TEA up to 250 and added all the Ascorbic acid and the Phenidone and it turned a pale yellow and has no smell at all. Humph ...
    Try it again! You're looking for deep black and evil smelling stuff!
    Tom Hoskinson
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    Everything is analog - even digital :D

  10. #30
    fhovie's Avatar
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    Perhaps it was the brand of tea I was using - is Lipton more evil than trader joes?? - maybe it is that I used the microwave ... no evil can enter the chamber of ionizing radiation?

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