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  1. #11
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    Quote Originally Posted by jdef
    Jim,
    you have a lot of experience with contact printing; how important do you believe that grain structure is in a negative for contact printing?
    I don't know. My first inclination is to answer that it doesn't make any difference. But if it doesn't, how would we explain the apparent "meta-sharpness" obtained by our friends who are showing prints made from negatives developed using the minimal agitation technique? Are edge effects caused purely by different perceptions of micro contrast, or does the minimal agitation technique affect the grain structure differently than say, constant agitation?

    Since grain is virtually invisible in my prints, I've focused on smoothness in the tones and not really paid much attention to the issue of grain, or even sharpness for that matter. The etched look is not really appropriate to the photogaphy I like to do anyway. That's why I haven't adopted the minimal agitation technique.

  2. #12

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    Jay, I do think we apply different standards for contact printing and for enlarging. I was talking about enlarging TP, I dont know how it would look in a contact print, other that its weird tonality I suppose the sharpness we see in contact prints would still be there regardless of the mushiness of the grain.

    For example there was some efforts by Durst to make a pt/pd enlarger and I think they did come out with an azo enlarger. Michael Smith is still involved in a azo enlarger. I dont know how successful these efforts will be, but on a personal note, I would not buy a pt/pd enlarger. I dont see the need for it nor do I think my photography would benefit from being able to enlarge in pt/pd. As I said in another thread, IMO the process is part of the final product, and the unique look of a contact print also plays a part in how we present our work.

  3. #13

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    Quote Originally Posted by jdef
    Jorge, I hope I didn't come across as contentious. You've been very inspirational to me, and I was just trying to answer some of my long standing questions for myself, and I couldn't pass up an opportunity to get your input on them. Thank you very much for your thoughtful consideration.

    Jay
    Not at all Jay, dont know what makes you think that....I was glad to give you my opinion, it is just that and hopefully it serves you in a small measure.

  4. #14

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    Quote Originally Posted by jdef
    The role of grain in accutance is fairly well known, and most printers recognize that prints with some apparent grain appear sharper than prints without apparent grain.
    What is sharpness?
    Let’s think of a dark grey object on a light grey background.

    Sharpness is a physiological phenomenon that can be tracked down to Detail Contrast. There are several ways to enhance Detail Contrast and thus enhance Sharpness.

    One is resolution. The higher the resolution, the more precise and harder can the borderline between the dark grey object and the light grey background been “modelled”.

    The second one is print contrast. Everybody knows that prints on higher paper grades usually look sharper than the same print on a lower grade paper. A low contrast scene like a tree in the fog remains relatively unsharp, even if taken on TP and print on a grade 5. Paper grade affects the difference between the dark grey object and the light grey background so that the eye and the brain recognise the borderlines worse or better. In the extreme cases, the light grey background becomes white and the dark grey object becomes black or both are mapped onto nearly the same grey tone on the print. Color contrast can do the same thing on a color print. The borderline between red and green is always sharper than, e.g., blue and violet.

    Acutance is a trick that increases the contrast directly at the borderline between the dark and light grey areas. Unsharp Masks and DIR-Couplers are other examples that work the same way. They aid the brain to better perceive the borderlines such that the image processor in our brain can calculate a clearer vision which makes us think that it look sharper. If you look at the MTF-Diagram in the Tech Specs of e.g. Kodachrome, you will see that at 5 lp/mm the output contrast is significantly higher than the input contrast, which means that this film is partially sharper than reality!

    Third, there is a certain, not exactly determinable, physiological phenomenon that makes us think that a coarse structure is sharper than a smooth one. This adds some virtual sharpness to a grainy print which is objectively not there.

    Quote Originally Posted by jdef
    1) How does grain structure affect the appearance of an image if it is invisible?
    It does not. Very small and invisible grain does increase resolution and thus provide a more precise way to separate things for the eye and brain. See above.

    Quote Originally Posted by jdef
    2) Would the apparent sharpness of a contact print be improved by visible grain?
    See third point above

    Quote Originally Posted by jdef
    4) How does grain structure affect edge effects?
    The sharper the edges of the grain the clearer are the borderlines between grain and no grain. Look at color film. Color film does not have grain. All the grain is removed in the bleach and fix. What is left are tiny dye clouds that have been developed together with the grain. On very high mag. ratios, these clouds look rather pointilisic with no edges at all.

  5. #15
    lee
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    jdef asked, " Lee,
    I understand that diffuse grain structure can degrade image sharpness compared to sharp visible grain. My question is; would the difference in grain between negatives made with Microdol X undiluted and Microdol X diluted 1:3 lead to sharper contact prints made from the 1:3 negative?"

    I suppose that is true but I don't really know the answer, Sorry. I don't particulary worry too much about sharpness of grain. I use Microdol-X as a contrast control with sodium metaborate. This is described in Ansel's book, The Negative.

  6. #16
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    I don't have too much to add - but I am so glad to be here ....

    Actually there are grainy films and grainy developers. I am not a big fan of grain but am a big fan of sharpness. Leaving out the discussion of 8x10 contact prints which are in my mind the gold standard, I could use TRI X in microdol or Pan F 50 in PMK. After trying several combinations, I like TRI X in Microdol better. The film provides the edgy grain and the developer lets me use it in 35mm or 120 format. HP5 in Microdol is a good alternative although the grain in HP5 is not as defined and in Microdol looses some of its bite.

    This really is a roll film discussion though - once you go 4x5 and up, grain and sharpness are fairly easy. I still am careful with TRI X in 4x5 - If I want to print big, PMK is a little coarse- PKHD seems better here.
    My photos are always without all that distracting color ...

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