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  1. #1

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    problem in developing sheet film

    Since some time, I am plagued by a very annoying problem when developing 8x10" sheet film for which I would really appreciate some advice. The problem is visible in the attachment, a scan of a negative which I brought back from my recent journey, and which is spoiled by it: look at the circular patches on the negative with a peculiar pattern inside, formed by respective areas of lesser density.
    The negative was developed in Sandy King's formula of Pyrocat HD (which I have used for years) in a separate dish into which it was transferred after 5 minutes pre-bath. 1st Minute continuous agitation, then once every 3 minutes, dev.-time: 16 minutes. I have developed 6 negatives in six dishes into which they were transferred, 2 at a time, from the pre-bath. When transferring I wore surgical dispensary gloves, and, this is how I can imagine the patches to be caused, I sometimes gently pressed the film into the developer, emulsion side up, with my gloved finger tips, to make sure it gets immersed.
    I have used this method for years, never encountered such problems until recently; on retrospect these patches seem to have started when I began using distilled water for the developer. They happen with both sorts of films I currently use (Ilford HP5 and Adox 100).
    By the way, I also develop 4x5" negs in a tank, and there I have never seen this problem.
    I would like to keep the distilled water, but obviously this problem would makes this prohibitive if it really causes the patches.
    Does anybody have suggestions, or has encountered such a problem her/himself?
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  2. #2

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    Film defect? You want to process an unexposed sheet in D 76 or the like to see if you get the same patterns.

  3. #3
    Nicholas Lindan's Avatar
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    Quote Originally Posted by Lukas Werth View Post
    circular patches on the negative with a peculiar pattern inside, formed by respective areas of lesser density
    My guess of the most likely cause is a dimpled bottom on the developing tray.

    You say you use gloves and press the negatives into the tray, and this could certainly be the cause but the pattern doesn't look like a set of fingers. If your gloves are powdered latex then some of the powder may be getting on the negative.

    Distilled water is not the culprit.
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  4. #4
    23mjm's Avatar
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    Finger prints while loading the sheet film into the holders?

    I to use tray development and have never seen such a thing. I don't use gloves and when I press the neg down it is just to submerge it not all the way to the bottom of the tray.

    I would try processing in a developer that you don't need gloves for and see if that makes a difference.

  5. #5
    JBrunner's Avatar
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    They look very much to me like the finger prints of a gloved hand, perhaps two fingers x 3 pushes.

  6. #6

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    Thanks for the replies which came up so far.
    My short answers:
    No film defect, as it occurs in two sorts of film.
    No dimpled bottom of the tray either, as only the backside of the film touches the bottom.
    The gloves are powdered inside (I think), but not outside.
    The patches also don't appear to be prints of naked fingers, as the pattern is different.
    And yes, they also appear to me like the prints of a gloved hand; but what could them make to appear? The latex of the gloves?
    I might text with distilled and non-distilled water, but I was hoping to find somebody who saw this before and might be able to give some advice before I start wasting my sheet films (though when I continue to develop my precious negs as I did, I am afraid I am also wasting them).

  7. #7

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    Try the Neoprene Gloves, they work great and are a pretty color purple. Oh yeah and they have no powder!
    PBrooks

  8. #8
    JBrunner's Avatar
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    Quote Originally Posted by Lukas Werth View Post
    Thanks for the replies which came up so far.
    My short answers:
    No film defect, as it occurs in two sorts of film.
    No dimpled bottom of the tray either, as only the backside of the film touches the bottom.
    The gloves are powdered inside (I think), but not outside.
    The patches also don't appear to be prints of naked fingers, as the pattern is different.
    And yes, they also appear to me like the prints of a gloved hand; but what could them make to appear? The latex of the gloves?
    I might text with distilled and non-distilled water, but I was hoping to find somebody who saw this before and might be able to give some advice before I start wasting my sheet films (though when I continue to develop my precious negs as I did, I am afraid I am also wasting them).
    You can get nitrile gloves that are not powdered at a medical supply shop, but I don't think that is the problem. The problem could be developer or fixer from a previous sheet on the glove fingers, or simply wet glove fingers contacting dry film before the presoak. I'm almost certain they are marks from gloved fingers.

  9. #9

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    Powdered gloves always end up with powder on the outside. Use the blue nitrile ones, no powder and after you put them on you might want wipe your hand/gloves with 98% alcohol to make sure there is no oil on them either. Could be you accidently touched your face after putting on the gloves, latex gloves will absorb oil like a sponge, esp if they are powdered.

  10. #10
    smieglitz's Avatar
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    On my monitor the areas appear to have a crescent shape at upper left within the round shapes. I've never seen anything like that before. My recommendation would be to change the type of gloves as others have suggested and to decrease the pre-soak time.

    Joe

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