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  1. #11

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    I believe that PE stated that graded papers use a "blend" of two emulsions to achieve the different grades. Now if these emulsions are equally responsive to the color of light hitting the paper, then no variation other than exposure should be noticed when printing with various papers, on the other hand, if these two emulsions had different responses to light, then you have Variable Contrast Paper.

  2. #12
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    Ah, but that is the problem.

    In graded papers, the papers have two contrasts, but the same spectral sensitivity, but in VC papers, they have two contrasts and different spectral sensitivities.

    So, this cannot explain the actual results posted.

    PE

  3. #13

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    I believe it was PE that said that Single Grade photo papers were made up of a "BLEND" of two emulsions (hard and soft) to achieve a specific grade. Now if both of these emulsions were equally responsive to the light, then using color filters would only affect exposure time, however if the emulsions each had a different response to light color, then you have Variable Contrast Paper. Perhaps there is some "minor" color sensitivity difference in the emulsions coated on single-grade paper that can be taken advantage of?

  4. #14

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    I am getting the impression that the consensus here is that "if your negative can be printed on single grade paper" then that is what is preferred.

  5. #15
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    Quote Originally Posted by mhv View Post
    How do you explain that behaviour? I know that contrast manipulation in VC paper is possible because of the two-plus emulsion layers that have different inherent contrast and different spectral sensitivity, but why does it work too on graded paper? I thought graded papers only had one characteristic curve, and that development was the only way to alter it.
    I can't give you a scientific answer why this happens, I just know that there are a number of tricks that can effect contrast either up or down. This is just one of them. If different chemistry can effect different levels of contrast than it doesn't seem impossible that different light sources could produce differences in contrast. Just the same as the shorter the time spent in developer will usually add warmth to the same paper, all other things remaining constant. These are subtle changes I am speaking of nevertheless they are tools we can take advantage of.

    The simple beauty of the black and white wet process lies in discovery.
    Real Photographs are Born Wet !
    http://www.steve-sherman.com

  6. #16
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    Steve, I've given this some thought. Could it be that there is a contrast reciprocity failure in here somewhere if the exposure times vary over a broad range?

    PE

  7. #17
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    Compare the cost difference between Graded and VC papers.
    Everytime I find a film or paper that I like, they discontinue it. - Paul Strand - Aperture monograph on Strand

  8. #18
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    What would happen if I used a negative with Yellow stain like from Pyrocat-HD and used the filters on graded paper?
    /matti

  9. #19
    Ole
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    Matti, in my experience you get extremely high contrast with stained negatives and graded paper. One reason why I rarely use staining developers...
    -- Ole Tjugen, Luddite Elitist
    Norway

  10. #20
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    Quote Originally Posted by Photo Engineer View Post
    Steve, I've given this some thought. Could it be that there is a contrast reciprocity failure in here somewhere if the exposure times vary over a broad range?

    PE
    This is as viable an answer as I can think of.

    The more I think about this, I remember that most of the contrast gain or lose is in the shadow values, the high values seem to remain the same.

    Don't discount staining developers, there are many more tricks to lessen contrast than there are to increase it.
    Real Photographs are Born Wet !
    http://www.steve-sherman.com

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