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  1. #1

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    HT-2 Hypo Estimator Query

    I recently bought a bottle of HT-2 Hypo Estimator, and my initial results have been puzzling. I have always washed for what I thought was an excessive length of time, and my motivation for introducing this test step was hopefully to cut down on water wastage.

    I am using the estimator chart that came with the solution, and it says I should be matching the spot colour to the estimator. The thing is, I'm getting a pinky hue in places that are close(ish) to patch 2 in colour, but the density can vary from one spot to another, and seemingly with the amount of solution I use having a direct effect. I understand that the paper could be clearer from one spot to another, but quite often the results are massively different.

    The guide also seems slightly contradictory, or at least unclear. For black and white processed paper 'the spot should have very little or no discolouration; that is, less than on patch one', and for Photographic Print Washing 'a stain that matches patch 2' is ok for all but 'longterm storage'.

    I am wondering what long term storage refers to in this instance (5 years, fifty years?) and whether a black and white fibre based print falls under the black and white processed paper, or photographic print washing category?

    I am also after some advice on reading the results, as a simple comparison to the estimator seems a little subjective - to me at least.

    As I said before, the quantity of solution effects the colour, and the time it is left on seems also to have a real effect. It seems I would have to wash forever to get a completely clear patch?!

    What sort of life expectancy might I expect from each patch, and what might a worst case deterioration look like if the spot matches patch 3. I have some untested prints that look good after 3 years... should I be concerned?

    This is a bit long winded and imprecise, but any observations or suggestions ( and hopefully reasurance )would be much appreciated.

    Thanks,
    Ciaran

  2. #2

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    Quote Originally Posted by Solarize View Post
    I recently bought a bottle of HT-2 Hypo Estimator,
    and my initial results have been puzzling.
    I wouldn't worry about the "processed" vs "washing".
    A little redundant on their part.

    First of all the HT-2 test does not indicate at archival
    levels. BUT no stain does mean very close to archival.

    The test is done drop wise. The silver within combines
    with any sulfur present in the emulsion. The stain is silver
    sulfide. The drop stays in place 3 minutes then is blotted
    off. The color must be read within a very few minutes
    of turning the lights up. The sulfide is light sensitive.

    Any further questions? Dan

  3. #3

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    Quote Originally Posted by dancqu View Post
    I wouldn't worry about the "processed" vs "washing".
    A little redundant on their part.

    First of all the HT-2 test does not indicate at archival
    levels. BUT no stain does mean very close to archival.

    The test is done drop wise. The silver within combines
    with any sulfur present in the emulsion. The stain is silver
    sulfide. The drop stays in place 3 minutes then is blotted
    off. The color must be read within a very few minutes
    of turning the lights up. The sulfide is light sensitive.

    Any further questions? Dan
    Light sensitive.... I am a dope

    There I was applying and checking it beside the window. Ok, so I fix and wash the print, and should I let it dry before testing? I had been experimenting on a dry print, and on the borders and image area. The stain intensified over time, confusing me further. Are subdued red light conditions ok for applying the drop?

    Thanks Dan.

  4. #4

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    Quote Originally Posted by Solarize View Post
    Light sensitive ...

    Ok, so I fix and wash the print, and should I let it dry
    before testing? I had been experimenting on a dry print,
    and on the borders and image area. The stain intensified
    over time, confusing me further. Are subdued red light
    conditions ok for applying the drop? Thanks Dan.
    One correction. The test solution contains silver nitrate.
    It is that which is light sensitive. The silver sulfide may
    or may not be light sensitive. Any body know?

    I test dry paper. Damp paper will allow bleeding
    of the drop causing dilution. Play with it some. IIRC
    I've used more than one drop, even stirred it some
    with a toothpick.

    I've a night light on, not to close by, when I apply. A dim
    white will be OK. Shadow while the drops soak in. I usually
    apply a few drops at half minute intervals then blot off
    in succession.

    How you use your fixer and your methods of washing will
    affect the thoroughness of the cleaning over the
    sheet as a whole.

    The HT-2 test is considered a valuable at home method
    of insuring clean prints at very near archival levels; no
    stain. Once a methodology is established, infrequent
    testing should do.

    I've some testing myself to do. I'll use multiple sheets,
    perhaps four, unexposed; through developer, fix and
    hold. Wash, drying, and testing follow. Dan

  5. #5
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    The HT-2 test area will brown up with time. None of my fixer test prints have clear border areas now due to that very fact. The browning varies from just detectable to intense depending on the amount of wash carried out.

    PE

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    Ciaran,

    I used a desk lamp with a 15W bulb pointed at the white wall of my darkroom when I performed tests with HT-2 recently.

    Tom.

  7. #7

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    Quote Originally Posted by Photo Engineer View Post
    The HT-2 test area will brown up with time. PE
    True, areas initially clear will slowly brown.
    I've tested Ilford's version of the HT-2 against
    Kodak's version. The results, Ilford's spot tests
    are sooner to brown and as time goes by they
    turn a darker brown than those of Kodak's.

    Ilford's is without the acidic acid; no more
    than a 1% solution of silver nitrate. Dan

  8. #8

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    Thanks everyone. This has cleared everything up and is a real releif. I am washing the prints enough.... phew!

    Ciaran

  9. #9
    Jim Noel's Avatar
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    Silver nitrate is not light sensitive until it comes in contact with an organic substance or is converted to another silver salt through chemical reaction. Wet plate photographers often "Sun" their silver nitrate to clear it of undesirable salts.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

  10. #10
    CBG
    CBG is offline

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    Quote Originally Posted by dancqu View Post
    True, areas initially clear will slowly brown.
    I've tested Ilford's version of the HT-2 against
    Kodak's version. The results, Ilford's spot tests
    are sooner to brown and as time goes by they
    turn a darker brown than those of Kodak's.

    Ilford's is without the acidic acid; no more
    than a 1% solution of silver nitrate. Dan
    Dancqu, can you say more about the Ilford test? Is it a published formula like Kodak's HT-2 or is it a packaged product? If it is a formula, could you post the formula here?

    Thanks!

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