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  1. #11

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    Working on it tonight. I just mixed up a fresh batch of XTOL so this test is timely. I will use 35mm TMY-2 as I believe you were doing your tests with that format.

    I would not compare curves to those obtained with Catechol, Pyro, and other low sulfite developers that work on the basis of controlled exhaustion. D-76 would be a better comparison.

  2. #12

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    Well, my first test won't be of any use. I hadn't used TMY2 with XTOL before, and hadn't used XTOL at stock strength before so I went with Kodak's recommended time of 6:30 @ 68F (which seemed very short) and Kodak's agitation recommendation. Way underdeveloped. I got the equivalent of N-3. I suppose I should have expected this since my TMX times with XTOL 1+1 are significantly longer than Kodak's.

    The shape of the curve did resemble Mark's upsweep, but with this degree of underdevelopment I can't come to meaningful conclusions regarding TMY2's normal curve shape in XTOL so I will have to redo this at least one more time.

    By the way my rolls are from the same batch as Mark posted.

    Apologies.

  3. #13

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    Quote Originally Posted by Michael R 1974 View Post
    Well, my first test won't be of any use. I hadn't used TMY2 with XTOL before, and hadn't used XTOL at stock strength before so I went with Kodak's recommended time of 6:30 @ 68F (which seemed very short) and Kodak's agitation recommendation. Way underdeveloped. I got the equivalent of N-3. I suppose I should have expected this since my TMX times with XTOL 1+1 are significantly longer than Kodak's.

    The shape of the curve did resemble Mark's upsweep, but with this degree of underdevelopment I can't come to meaningful conclusions regarding TMY2's normal curve shape in XTOL so I will have to redo this at least one more time.

    By the way my rolls are from the same batch as Mark posted.

    Apologies.
    Michael, I suspect something went wrong. I develop TMY2 the same way you did: XTOL (stock) at 6:30 @ 68F, but agitating less than you, and I get normal density and a normal CI of 0.57. What's the density of your leader? Mine is 2.76, which is higher than most films.

    YIKES! I just remembered another detail: I always pre-soak the film! I discovered a year ago that TMY2 gives higher densities when pre-soaked. I give it 4 minutes agitating twice per minute. Sorry, I should have mentioned this earlier. But even so, the lack of a pre-soak should not cause an N-3 pull.

    Anyway, your test is probably useful because I've noticed that under/overdevelopment does not change the shapes of curves much. Could you post your numbers or graph? BTW, thanks for doing these tests!

    Mark

  4. #14

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    That is disturbing to say the least. I have always needed significantly longer times than Kodak recommends for XTOL/TMax films, and my times have always been consistent. I have no explanation for this. Perhaps someone else should run the tests.

  5. #15

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    Quote Originally Posted by Michael R 1974 View Post
    That is disturbing to say the least. I have always needed significantly longer times than Kodak recommends for XTOL/TMax films, and my times have always been consistent. I have no explanation for this. Perhaps someone else should run the tests.
    In addition to a pre-soak, here are a couple more ideas:

    * Inaccurate thermometer (are all times longer than expected?).
    * Something in tap-water damages XTOL. (BTW, I use distilled water because my tap-water is hard).

    If you don't mind running another test, you could do so using your times and process that are known to work. But AndreasT and you have already reported upswept curves, so maybe we already know what the result of another test would be...

    Mark

  6. #16

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    Tmax gets the straightest curve with TMRS developer. But TMX can shoulder off if overexposed in full range lighting; and that's a reason it should not be rated below box speed with certain common developers. Some developers will create an upswept curve at the top with TMY, but you've really got to
    be up there where you don't belong to begin with. I've used a variety of developers with these films, but never XTol - and if Xtol does in fact predictably produce a toe like that, I wouldn't even want to
    bother with it.

  7. #17

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    Quote Originally Posted by albada View Post
    In addition to a pre-soak, here are a couple more ideas:

    * Inaccurate thermometer (are all times longer than expected?).
    * Something in tap-water damages XTOL. (BTW, I use distilled water because my tap-water is hard).

    If you don't mind running another test, you could do so using your times and process that are known to work. But AndreasT and you have already reported upswept curves, so maybe we already know what the result of another test would be...

    Mark
    Thermometer is certified/calibrated, and I use distilled water for all chems. XTOL/TMax films is the only combo for which my times are long (regardless of dilution - stock, 1+1, 1+3). Curiously with Delta 100 my times are pretty close to Kodak's, and that's with less agitation than Kodak. Very strange. I will redo but I'm sure I'll get the same results as my process is tightly controlled. Perhaps I exposed incorrectly.

  8. #18

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    Quote Originally Posted by Michael R 1974 View Post
    Thermometer is certified/calibrated, and I use distilled water for all chems. XTOL/TMax films is the only combo for which my times are long (regardless of dilution - stock, 1+1, 1+3). Curiously with Delta 100 my times are pretty close to Kodak's, and that's with less agitation than Kodak. Very strange. I will redo but I'm sure I'll get the same results as my process is tightly controlled. Perhaps I exposed incorrectly.
    Do the edge-markings look thin? If so, your exposure is probably fine. Anyway, it would be interesting to re-try the process with an added pre-soak and/or longer time.

    Quote Originally Posted by DREW WILEY View Post
    Tmax gets the straightest curve with TMRS developer. But TMX can shoulder off if overexposed in full range lighting; and that's a reason it should not be rated below box speed with certain common developers. Some developers will create an upswept curve at the top with TMY, but you've really got to
    be up there where you don't belong to begin with. I've used a variety of developers with these films, but never XTol - and if Xtol does in fact predictably produce a toe like that, I wouldn't even want to
    bother with it.
    Drew, you bring up some interesting points. (1) Like you, I've seen TMX shoulder-off and also recommend that it not be overexposed. But my latest concentrate makes it shoulder-off too soon, so I'm wondering whether to do anything about that. (2) My TMY2 curves in the OP shows the upsweep starting in the upper midtones or low highlights, so it'll affect folks (assuming it's not due to my own goof). Maybe it started farther out in prior batches. (3) The toe of TMY2 looks sharper than most to me; what about it do you dislike?

    Mark Overton

  9. #19
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    T-Max 400 has boomerang curve

    So, how do you guys measure this stuff? Like can you explain the process if messing a curve? Do you scan it with a special program or how do you plot it?

    Thanks.


    ~Stone

    Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk
    ~Stone | "...of course, that's just my opinion. I could be wrong." ~Dennis Miller

  10. #20
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    Stone,
    Google densitometer.
    Its a machine that measures silver densities directly off the film.

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