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  1. #1

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    Increasing Graded Paper Contrast

    I have no experience working with graded paper and need advice on raising print contrast. I am working with an image I wish to display printed on Galerie #3 developed in Dektol 1:2. The test print image is 1/2 or so grade too soft. Do I under expose and over develop to raise contrast?
    RJ

  2. #2
    jmdavis's Avatar
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    Quote Originally Posted by Richard Jepsen View Post
    I have no experience working with graded paper and need advice on raising print contrast. I am working with an image I wish to display printed on Galerie #3 developed in Dektol 1:2. The test print image is 1/2 or so grade too soft. Do I under expose and over develop to raise contrast?

    Maybe you could try a more active developer combined with a longer print development time. Selenium may help some as well, but I figure that you already know about that.

    Mike

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    David A. Goldfarb's Avatar
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    You could also intensify the neg. Kodak Rapid Selenium Toner 1:3 for about 8 minutes should get you about a one zone contrast boost.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
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  4. #4

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    Increasing the contrast of graded paper is very difficult. the easiest thing to do is move to a higher grade and use a water bath.

    Sincerely;
    [FONT="Book Antiqua"]Christopher Breitenstein[/FONT]<br>

    Http://www.wetlabphotography.com

  5. #5
    Ian Grant's Avatar
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    Raising the Contrast ½ a grade is relatively easy, all the manufacturers used to publish formulae, Ilford ID-14 would easily give you more than enough increase in contrast.

    Ilford recommended Dr Beer's variable contrast developer for Galerie, and published the formula in the 1982 Ilford Galerie technical information sheet.

    Ian

  6. #6
    Ole
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    Extending development WILL help. Adjusting exposure MAY be a good idea.

    Using a high-contrast developer WILL help.

    Adding a little KBr (or benzotriazol) to the developer will hold back the highlights a little, resulting in higher contrast. Adding more alkali to the solution MAY enhance this.

    Since you use Dektol at 1:2, try first using it full strength.

    Changing the contrast of a graded paper by +/- 1 1/2 steps is easy, more than that requires creative thinking.
    -- Ole Tjugen, Luddite Elitist
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  7. #7
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    I agree, getting another 1/2 grade increase in contrast is not hard. Don't believe Gallerie Grade 4 is an option any more.

    First I would try increased development time. You may want to reduce the exposure just a tad, but try extending the development time first.

    Second, use Dektol 1:1. Between this and extending the development, you should be able to do it without too much fuss.
    Semper Fi & God Bless America
    My Photography Blog

  8. #8
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    In such a situations I usually make the print on the dark side in order to get good blacks, then I immerse the whole print in diluted Farmer's Reduces in order to clear the whites. With such a procedure you gain also a spectacular highlights separation, sometimes I do it only for this.
    Attached Thumbnails Attached Thumbnails SCALA_Pyrocat_Fortezo_Ansco130.jpg  
    Last edited by karavelov; 06-19-2008 at 06:16 AM. Click to view previous post history.

  9. #9

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    If you use Dektol 1+2 and give it adequate development time to reach completion, it is not very easy to boost image contrast much farther by changing the exposure or development, unless you use one of the high contrast developers used for printing films (those usually contain hydrazine derivatives, tetrazolium derivatives and amine contrast boosters). These developers are relatively recent technology and currently not used in b&w pictorial printing.

    Film emulsions are usually partially developed and so extended development can give contrast boost (though there is a limit called gamma infinity). On the other hand, print emulsions are designed for complete development, unless you go to the classic warmtone development, which slightly underdevelops the emulsion with a bit of overexposure. So you can't really "push" papers like you can with films.

    A small contrast enhancement in highlights can be made by adding benzotriazole (BTA; 200-500mg/L) or 1-phenyl-5-mercaptotetrazole (PMT; 10-40mg/L) to the developer. PMT is more powerful but wears out of the solution faster than BTA. This is more effective to do with Dektol 1+1 rather than 1+2. But stock strength Dektol may or may not work well depending on the paper emulsion.

    A noticeable contrast enhancement in shadows can be made by applying a selenium or polysulfide toner, until you see just noticeable change in the image hue but not much more. It often happens that the further increase in shadow density is observed a day or two after drying in the case of polysulfide.

  10. #10
    Ian Grant's Avatar
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    Great verbiage Ryuji, but is it remotely relevant

    Ian

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