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  1. #31
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    Quote Originally Posted by Michael W View Post
    Only in the image. Unexposed areas are clear.
    Ok, then the observation is that random spots in the image appear to have experienced hyperdevelopment of a currently unexplained origin.

    Places with little or no latent image have little effect, while areas with significant exposure exhibit significant effect.

    Or, as you originally said, it is proportional to density.

    Correct?
    Michael Batchelor
    Industrial Informatics, Inc.
    www.industrialinformatics.com

    The camera catches light. The photographer catches life.

  2. #32

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    Quote Originally Posted by michaelbsc View Post
    Ok, then the observation is that random spots in the image appear to have experienced hyperdevelopment of a currently unexplained origin.

    Places with little or no latent image have little effect, while areas with significant exposure exhibit significant effect.

    Or, as you originally said, it is proportional to density.

    Correct?
    Yes, that's correct.
    I think my suggestion of stop bath being a possible cause was a red herring. I only mentioned it because I never use acid stop and only decided to on a whim so when I saw the spots I thought it might be a factor.
    It's something about the developer. It was a newly opened bottle of Adox Adonal from the batch that landed in Sydney a couple of weeks ago. Diluted 1:50, normal inversion agitation in a Paterson tank. The PM I received said that Rodinal type developers are known to do this.

  3. #33

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    Quote Originally Posted by trexx View Post
    My first post, way back at the start should have been
    "This look like light scatter in Pinhole photography, was this a pinhole?"

    I thought it, and should have added it to my questions of processing. When I was doing a lot of pinhole I saw them all the time. Even in when not pointed at a strong light source.

    One thing maybe to prove this to you is that you can find the same pattern on different frames. Now one roll may not be enough to see, But on the hundreds of pinhole frames I have done I could see similar patters of black spots.
    How might this occur?

    Finely suspended dust particles inside the camera imaged by the infinite depth of field of the pinhole and reflecting light, like dust in beams of sunlight?

    Less than perfectly smooth edges of the pinhole?

    The first would lead to varying patterns, the second (if operative) would lead to identical patterns from picture to picture (when conditions bring it out). Your post was ambiguous. Are you saying the patterns of dots are in the same position from picture to picture (when conditions are right to create them)?

  4. #34
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    Quote Originally Posted by Monito View Post
    How might this occur?

    Finely suspended dust particles inside the camera imaged by the infinite depth of field of the pinhole and reflecting light, like dust in beams of sunlight?
    no
    Less than perfectly smooth edges of the pinhole?
    Yes and nothing can be perfectly smooth. When I make pinhole with the dimple and sand method these patterns are easily seen. With my Zero Image it is less evident, but can still be seen.
    The first would lead to varying patterns, the second (if operative) would lead to identical patterns from picture to picture (when conditions bring it out).
    yes, flares around highlights will produce similar patterns. I think this is called diffraction.
    Your post was ambiguous. Are you saying the patterns of dots are in the same position from picture to picture (when conditions are right to create them)?
    Yes similarities in these patterns can be seen. Not necessarily the exact dot pattern, dot for dot in the same place. Sometime a ray of dots that varies in density, or a cloud of dots taking on the same shape.

    Sorry that I cannot explain better, this is only from observation, no scientific rigor on my part.
    D-76 is a standard developer, although not one I use.
    Ansel Adams - The Negative

  5. #35

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    Dear Michael W,

    Firstly, I do not know if anyone from HARMAN has come back to you yet, regardless its not a problem, I will sort it.

    I have checked if we have any QC's pending, we have none on any film at present. I have seen 'black spot' before and it can have various causes, never say never but I can virtually guarantee its not the film, but we need it back at the factory to make absolutely sure, and check it under the electron microscope to explain what actually caused it, and what it is.

    As to PAN F+ being 'fragile'..... I do not know where that came from, PAN F+ is not fragile, I do know all the manufacturing parameters regarding the physical structure and performance of our films and PAN F+ is as robust as all our other emulsions.

    So please pm me with your details : And send the exposed film to us in the UK marked for my attention and I will ensure tech service look at it for you, and of course give you an explanation

    Simon ILFORD Photo / HARMAN tcehnology Limited :

  6. #36

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    Hi Simon, good to hear from you. I will PM to organise sending the film.

  7. #37

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    Thanks trexx for the clarifications and the greater detail of your experience. I find it very interesting the myriad ways that inaminate objects have of perversely injecting anomalies into our best efforts!

    Based on trexx's posts and Simon's post, I would say that the pinhole issue is the leading suspect currently.

  8. #38
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    Quote Originally Posted by Monito View Post
    Thanks trexx for the clarifications and the greater detail of your experience. I find it very interesting the myriad ways that inaminate objects have of perversely injecting anomalies into our best efforts!

    Based on trexx's posts and Simon's post, I would say that the pinhole issue is the leading suspect currently.
    Ok, then there is a mechanism which can produce localized excessive exposure when using a pinhole? And rather than over development this may be a case of exposure anomolies?

    Assuming this is in keeping with Simon's finding, can anyone explain the phenomena in a way that we can exploit it or avoid it?
    Michael Batchelor
    Industrial Informatics, Inc.
    www.industrialinformatics.com

    The camera catches light. The photographer catches life.

  9. #39

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    Your black spots might be related to “pepper fogging”. This is reportedly more often seen in the development of lith films and in lith printing, aerographic films, but might also be seen in regular films as well. I also found a reference to it happening with the now obsolete Kodak HIE film, but I suppose it could happen with any film under the right circumstances.

    It’s related to the process, not the film. The developer might be a suspect.

    http://www.kodak.com/ek/US/en/Pepper_Fog_Spots.htm

  10. #40

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    Look at the bottom of your fix bottle. Silver precipitates out from used fix starting in a day or so. They appear mostly as flakes , not round spots although some are round. They stick to the next film like glue, more to the denser area, but can be abraded off carefully if film is still wet. Once dry , forget it.

    I have never found a home filtering procedure to remove the silver perfectly. Bounty brand towels quartered in a funnel will filter off the bigger pieces. MUST be Bounty, nothing else.

    I never reuse fix on important film and I do filter and use it up on test prints.

    Get a glass bottle and clean it out and use it for fix.

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