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  1. #1
    schrochem's Avatar
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    Black Stains - Lith printing

    I'm having some success with prints from wet plates. However, last night I got these huge black stains.
    The first three prints were fine (from two different plates). I go to make my fourth print with a different plate and one area starts to develop out first (5 or 6 minutes in). By the time the rest of the print is ready, that area is a black mass.
    I printed the thing a total of 4 times with similar results. The stain was in the same general area but not exact. From my search I see it's usually from the print getting air and oxidizing in that area or poor agitation. On the second through fourth, I made sure that wasn't a variable.
    The things I tried:
    Added fresh developer
    Made sure my red headlight wasn't a problem.
    I thought perhaps the new 25W bulb I'm using was an issue. I tilted it to a different part. I also reduced/increased exposure a bit.

    The only other thing I can think is its the plate itself. I ran out of time to go back and try one of the early plates.
    That was a real pity.
    I do a good job at cleaning the back of the plate but maybe there is an area clearer than the rest?
    This is an unvarnished plate so maybe that is causing a 'hot spot' and not an even exposure?
    However, the other plates were the same and taken at the same time......
    As far as the light bulb, this one is a soft white. I don't think it really matters but I am curious if it's a factor.
    Do I need to try to diffuse it evenly some how? It seems even looking at the table.....

    Anyway, any and all comments will be muchly appreciated.
    I really wanted to see this print in it's entirety. The rest of it I liked.

    Chemistry:
    Easylith 30ml:35ml:1L
    Then I added 15ml:15ml:500ml to see if that would help.
    Paper is fomabrom
    Exposure was 3-5s
    Thanks
    Scott

  2. #2
    schrochem's Avatar
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    I did have a little flake of collodion get in the developer. That couldn't have ruined it??? Even if I did have bad developer could it create this stain in roughly the same spot every time?
    Scott

  3. #3
    schrochem's Avatar
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    If anyone lands on this page in the future, my problem was agitation. It seems rocking the tray wasn't enough. I have to agitate with the developer with the tongs and there is no issue. I think it has to do with a stronger dilution than my first two sessions.
    Scott



 

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