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  1. #11
    Silverpixels5's Avatar
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    The process of washing film or prints with several water changes works just as well as a running water bath. The concentration of the fixer and its by-products in the paper is going to want to move into the free water of the bath in order to balance things out. After the 3rd or 4th water change, there really isn't much of anything left.

  2. #12

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    Quote Originally Posted by Max Power
    ...But I just don't see how four flushes can compare
    to 5 - 10 minutes of constant flow
    The problem with constant flow is it's more laminar nature.
    Eddies are produced which will leave areas of a film's surface
    in 'still' water. That is one of the big problems of archival
    print washers.

    I use the Ilford method but with four washes counting the
    last which has a bit of Photo Flo. Distilled water at ROOM
    temperature is used. For the four 1.5 +/- liters will do.

    It is only the gelatine that needs the wash time and it
    comes clean by way of diffusion. Dan

  3. #13
    titrisol's Avatar
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    This is a problem of chemical reaction engineering.
    I can;t remember the differential euqations in play here, but you can do a test:

    Wash a glass with a LOT of soap, and suds
    How will the glass be cleaner faster?
    - By using a stream of water for XX minutes
    - or by using 4 or 5 changes of water with 1/2 the volume of the glass???

    Try it and decide yourself
    Mama took my APX away.....

  4. #14

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    Quote Originally Posted by Silverpixels5
    The process of washing film or prints with several water changes works just as well as a running water bath. The concentration of the fixer and its by-products in the paper is going to want to move into the free water of the bath in order to balance things out. After the 3rd or 4th water change, there really isn't much of anything left.
    Hi !
    I do agree !
    A French laboratory has made tests for museums trying to define an "archival standard" for washing prints to be sold/stored in museums.
    The prouved that one wash more efficiently by moving prints from a tray of water to a tray of fresh water and repeating 5 times than letting print soak in an archival water, whatever flow rate. They have also shown that the less the prints are in contact wih water, the longer they will keep. They have done their experiment very preciselly and in a complex fashion, because they measured the total amount of hypo left in the paper sheet. They have produced a set of documents for professional printers (I've seen and read them during a printing workshop done by a French renowed (sp ?) printer but forgot to note the reference... Grrr . Laziness, always....
    When young, I've been told to follow the Ilford washing sequence ans can show negatives from the 70's which are fine.... well in this respect, because for artistical matters, ,-)

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