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  1. #21

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    Alternatively, you could check your fix for any undissolved crystals.

  2. #22
    Usagi's Avatar
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    I have had similar problems with some films and developers (mainly hp5+ and fp4+, D-76 and Xtol) over years. Not as bad though, only one or two small "pinhole" in the negative.
    I never had figured out what is the reason, I have tried all tricks but nothing works so I take always 3-5 frames per each subject to ensure that I have at least one fine negative.

    My best guess so far is that "pinholes" are caused by undissolved crystals of the developer.
    Last edited by Usagi; 10-03-2007 at 06:39 PM. Click to view previous post history. Reason: Added dissolve guess..

  3. #23
    HeliH's Avatar
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    Quote Originally Posted by Usagi View Post
    My best guess so far is that "pinholes" are caused by undissolved crystals of the developer.
    Terve Jukka ,

    Well as I already told, I checked my developer and at least I can't find any undissolved crystals.

    But yesterday I found out that my other tank has some dry fixer in the bottom. It's very possible that this tank where I developed this film, had also dryed fix in there... Could it be the reason?
    - Heli

  4. #24
    Thomas Bertilsson's Avatar
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    Heli, do you know the pH of your fixer solution? I would think that if it's acid it would possibly matter, since the 'specks' on your film is blank, something prevented development from taking place in those spots. Perhaps it's some sort of local contamination by crystals of dry fixer that stuck to the emulsion during the pre-wetting stage, fixed those specks clear before development took place? Is that a possibility?
    Try alkaline fixer. I've developed both FP4 and HP5 in pyrocat without problems, but I always use neutral or alkaline pH fixer.
    - Thomas
    "Often moments come looking for us". - Robert Frank

    "Make good art!" - Neil Gaiman

    "...the heart and mind are the true lens of the camera". - Yousuf Karsh

  5. #25

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    Those look like pin holes in the emulsion. the tell-tale halo gives them away. I occasionly have the same problem.

    Gordon Hutchings, "The Book of Pyro" should provide a remedy.

    Yours;

  6. #26

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    In one sense, this is a simple problem. Black spots on prints = reduced density on the negative. Any residual bits that might have embedded themselves into or onto the film, even though they may look white to the eye, will block light and result in white spots on the print. You can pretty much rule that out as an explanation for your problem.

    I have never used an alkaline fixer. The closest to it is Kodak's C-41 fixer which is near neutral. I alway use an acid stop bath unless the developer specifically calls for its replacement with a water rinse, as is the case with Diafine. Despite all that, I have never seen a pinhole that was caused by using an acid stop. A true pinhole, where the emulsion has physically separated from the support will be apparent by visual and tactile examination. Use a loupe for visual inspection, and feel the emulsion with your fingertip. If there are surface irregularities, then you have separation. If not, then something else is wrong. That something else could be as simple as dust settling onto the emulsion before exposure, though that is unlikely considering the almost perfectly round shape of the spots.

    In my opinion, the most likely cause of your problems is air bells. Small air bubbles attach themselves to the film and are not dislodged by agitation. Developer doesn't reach the emulsion, and no development takes place. Result - clear spots on otherwise undamaged negatives that print black.

    I've found that it's best to use water that has at least rested, and this is especially true if your tap has an aerator, so that some of the dissolved gasses dissipate. Heating the water will drive off most if not all the dissolved gasses. Just be sure to let it cool before use. Always stir, never shake, to mix chemistry. Shaking always introduces air into the mix and that's never good on a couple of levels. And don't forget agitation. Proper agitation wil dislodge any air bells clinging to the film. There are a lot of folks who advocate gentle agitation. Don't buy it. I have never seen surge marks caused by vigorous agitation. I have never seen uneven development come out of a rotary processor, provided it contained a sufficient volume of chemistry, like the Jobo which agitates constantly. I have seen what looks like surge marks around sprocket holes on 35mm film from insufficient agitation.
    Last edited by fschifano; 10-07-2007 at 10:46 PM. Click to view previous post history.

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