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  1. #31
    gainer's Avatar
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    Quote Originally Posted by jdef
    That's great information, but what is A1?
    OOPS!

    Didn't take long enough.

    A1 was:

    100 ml propylene glycol or glycerine or ethylene glycol
    10 g ascorbic or erythorbic acid
    0.25 g phenidone

    Heat till dissolved.
    Gadget Gainer

  2. #32

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    Quote Originally Posted by jdef
    I've been meaning to try adding a little metol or phenidone to the P-TEA, but I have only gone as far as to mix it 50/50 with the PG/PQ concentrate, which produces an entirely different developer from either of the "parent" developers. Regarding Cat-P-TEA; could one substitute hydroquinone for the catechol?

    Well, I had been meaning to try the Pyro-TEA formula for a while and finally got around to it today. I mixed two separate solutions of the Pyro-TEA formula, which I will call P-TEA and PM-TEA.

    P-TEA
    TEA, 100ml
    Pyrogallol, 10.0 g

    PM-TEA
    TEA, 100ml
    Pyrogallol, 10.0g
    Metol, 2.0 g
    Bromide, 0.2g

    I exposed two sheets of Ilford FP4+ film to a Stouffer step wedge for the same time, then developed one in P-TEA, and a second in PM-TEA for ten minute, using a 1:50 dilution. The pH of the working solution was 9.1. By contrast a working solution of PMK 1:2:100 has a pH of about 8.6, while a working solution of Pyrocat-HD has a pH of about 10.9.

    As soon as the processed negatives dried I read the densities in Blue channel and plotted the curves. Then I compared the curves with existing curves of the same film and time of development in PMK and Pyrocat-HD.

    Here are my conclusions based on reading of the curves in terms of developer energy, EFS and B+f. I won't comment on grain and sharpness since it is really not possible to evaluate these qualities in step wedge tests.

    Developer Energy -- Pyrocat-HD (1.1:100) and PM-TEA (1:50), were almost identical in terms of energy. The step tablet densities at ten minutes of development were almost identical for both developers. PMK 1:2:100 was next in energy, but quite far behind both PM-TEA and Pyrocat-HD.
    Regular P-TEA, at 1:50 required the longest development time of all.

    EFS -- Comparing curves of all four developers gave the following results. Pyrocat-HD, EFS = 125, PM-TEA and PMK, EFS = 100, and P-TEA 70, EFS = 70.

    B+f --Pyrocat-HD and PMK, both log 0.06 in blue channel. PM-TEA, 0.14, and P-TEA, 0.18.

    I did not compare curves with UV reading but can note that the color of the stain of PM-TEA and P-TEA is very similar to PMK with film, on the yellowish side, while the Pyrocat-HD stain is distinctly brown.

    My conclusion is that P-TEA can be measurably improved in energy and EFS by the addition of metol, and both P-TEA and PM-TEA need some bromide to reduce B+F.

    Sandy
    Last edited by sanking; 08-13-2004 at 10:12 PM. Click to view previous post history.

  3. #33

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    Sandy,
    How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?
    Tom Hoskinson
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    Everything is analog - even digital :D

  4. #34
    clay's Avatar
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    Quote Originally Posted by Tom Hoskinson
    Sandy,
    How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?
    And excuse me if this question has been answered on some thread in some other forum, but where does one purchase TEA?

  5. #35

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    Quote Originally Posted by Tom Hoskinson
    Sandy,
    How did you get the metol into the TEA? Did it dissolve directly into the TEA? If so, at what temperature did it go into solution?
    Tom,

    I poured the pyrogallol (pyrogallol + metol + bromide for the PM-TEA formula) directly into the TEA at about 250 degrees F. Everything dissolved quickly with just a couple of minutes of stirring.

    The resulting solutions were a dark purplish/brown in color. The working solutions from both formulas were medium amber in color, just a tad darker than PMK working solutions. But when I discarded the used developer it was very darkish brown, much more so than I have seen with PMK. But the negatives came out ok, albeit with slightly more B+f than I like.

    Sandy

  6. #36

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    Quote Originally Posted by clay
    And excuse me if this question has been answered on some thread in some other forum, but where does one purchase TEA?

    Clay,

    http://www.chemistrystore.com/

    Great site that I first learned about from Michael Mutmansky.

    Sandy

  7. #37

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    Quote Originally Posted by sanking
    Tom,

    I poured the pyrogallol (pyrogallol + metol + bromide for the PM-TEA formula) directly into the TEA at about 250 degrees F. Everything dissolved quickly with just a couple of minutes of stirring.

    The resulting solutions were a dark purplish/brown in color. The working solutions from both formulas were medium amber in color, just a tad darker than PMK working solutions. But when I discarded the used developer it was very darkish brown, much more so than I have seen with PMK. But the negatives came out ok, albeit with slightly more B+f than I like.

    Sandy
    Thanks very much, Sandy. This is a very useful piece of information.

    I had tried dissolving metol in several of the alchohols and glycols without success - but I had not tried it in TEA. I guess it likes the alkalinity provided by TEA.

    Your result suggests to me that Glycin may also be soluble in TEA - I'll try it out (Glycin is described as freely soluble in alkaline solutions).
    Tom Hoskinson
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  8. #38
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    Okay, I mixed up a small batch of CAT-P-TEA, with a little added bromide, and everything went into solution at 220-230 degrees. I tried to mix up some PM-TEA, at the same temperature, and the metol never went into solution. Is there a trick here that I am not privy to?

  9. #39

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    Quote Originally Posted by clay
    Okay, I mixed up a small batch of CAT-P-TEA, with a little added bromide, and everything went into solution at 220-230 degrees. I tried to mix up some PM-TEA, at the same temperature, and the metol never went into solution. Is there a trick here that I am not privy to?
    You may need to take the TEA to a higher temperature. When I did this the metol went into solution almost immediately but I mixed at a higher temperature. I wrote 250º F but in fact my TEA solution was probably even hoter than that because the temperture was at 250º F and still rising when I quit measuriing. It might have been as high as 280-300º.

    Sandy

  10. #40
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    Quote Originally Posted by sanking
    You may need to take the TEA to a higher temperature. When I did this the metol went into solution almost immediately but I mixed at a higher temperature. I wrote 250º F but in fact my TEA solution was probably even hoter than that because the temperture was at 250º F and still rising when I quit measuriing. It might have been as high as 280-300º.

    Sandy
    It's been years since i mixed up PMK, and it just occurred to me: was I supposed to dissolve the metol BEFORE the pyrogallic acid? I seem to remember that the metol is supposed to go in first. I did it the other way....

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