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  1. #11
    Gary Holliday's Avatar
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    Coming out of an ice age I'd like to think so...until the next wax and wane of the ice sheet.

  2. #12

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    Quote Originally Posted by Gary Holliday View Post
    I was hoping to be a little bit more economic with my wash water for 120 films. I've read the Ilford agitation technique for films, but feel a little bit nervous doing that.
    The most important thing to do in using Ilford washing process is to follow their instruction very carefully. You want to use non-hardening rapid fixer and you want to give at least twice the clearing time. Their washing process may be greatly shorter than what you hear elsewhere, but that's partly because of practice from old days where everyone used hardening fix. Many darkroom chemistry authors are not familiar with the technical issues and they also just cut and paste old instructions (that they are used to). I have tested Ilford washing methods with several non-hardening rapid fixers and I get residual thiosulfate level well below the ISO archival standard for life expectancy greater than 500 years. You don't need to worry about amateur opinions on APUG threads; trust Ilford on this one.

    In flowing water and dunking the film, what could be my minimum wash time?
    If you use continuous flow washing, the time it takes is strongly dependent on how vigorous the agitation is. Usually, most washers rely on the water inlet flow to agitate the washing water and this is far less vigorous than inverting tank by hand. So you'll need 5-10 minutes to be safe. But if you give good manual agitation on top of flowing water, the washing time of 1-2 minutes already exceeds the archival standard.

    http://wiki.silvergrain.org/wiki/ind...val_processing

    The current standard is ISO 18901:2002 as summarized in the page above.

  3. #13
    Photo Engineer's Avatar
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    Gary;

    Dr Mason of Ilford labs has effectively repudiated the Ilford method in his textbook "Photographic Processing Chemistry". Please see my long explanation of it if you wish on that other thread. Basically, it involves a lot of math not needed here, but the bottom line is one of my last points there.

    The famous photographer Ctein was blindsided by what he thought were archival prints. He had to replace prints for some customers and wrote an article about it pointing out that if you do things wrong it may take a long time to see if you over or under washed. There is a sweet spot in washing that the experts recommend.

    I think it is foolish of us to ignore all the years of experience of those who went before us, for the advice of anyone who has not conducted the experiments for himself, or someone who has not had long term keeping results of their own to view.

    PE

  4. #14
    Gary Holliday's Avatar
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    Not wanting this thread to develop into a battle of photographic chemistry theories, I'm looking for a practical method for washing that everyone can relate to.

    It's clear that Ilford's method is fairly controversial, so practical alternatives are what I'm hoping for.

    I was originally taught (many years ago) to wash in flowing water, exchanging the water regulary for 20 mins.

    I use Ilford Hypam at present, so needed advice on a shorter wash time.

  5. #15
    Photo Engineer's Avatar
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    To summarize my viewpoint:

    Kodak's recommendation for film has been unchanged since the early days for acid fix, and that is 5 - 6 changes of water over 30' with agitation. For FB papers it is 10 - 12 changes over 60". RC paper or alkaline fixes will take shorter times as suggested on the recent fixer packages themselves.

    The key according to all my experience and all the textbooks I have read is to have some sort of flow and/or agitation, whatever means or time is used.

    Selenium toning helps, but wash aids require washing themselves.

    You must take care to not overwash.

    PE

  6. #16
    jstraw's Avatar
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    How fine is the line between adequate washing and overwashing? What constitutes overwashing (what's being washed out that shouldn't be?)? What are the consequences?
    Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In velit arcu, consequat at, interdum sit amet, consequat in, quam.

  7. #17

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    "A Practicle Method For Washing that Everyone Can Relate To"

    Quote Originally Posted by Gary Holliday View Post
    I'm looking for a practical method for
    washing that everyone can relate to.
    a shorter wash time.
    Perhaps my post #4 this thread went unread. The method
    described in that post is "a practical method for washing that
    everyone can relate to" Takes about 10 minutes and for a 120
    roll uses only 2 liters of water; that with a final Photo Flo rinse.
    Keep some room temperature water on hand. It will speed
    diffusion and make for a more thorough wash.
    I suggest post #4 be given a read.

    As I believe it is practiced the running water method is a big
    waste of water and time; 20 minutes? Dan

  8. #18
    Photo Engineer's Avatar
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    Quote Originally Posted by jstraw View Post
    How fine is the line between adequate washing and overwashing? What constitutes overwashing (what's being washed out that shouldn't be?)? What are the consequences?
    I think overwashing would be 1.5x to 2x or more of the manufacturers recommendation.

    As far as Dan's method goes, as long as there are 5 or more changes with a hold in between along with agitation, that is not inconsistant with what I said.

    PE

  9. #19

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    [QUOTE=Photo Engineer;461223]
    "...as long as there are 5 or more changes..."

    What happened to the three five minute soaks? Dan

  10. #20
    Michel Hardy-Vallée's Avatar
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    Quote Originally Posted by jstraw View Post
    How fine is the line between adequate washing and overwashing? What constitutes overwashing (what's being washed out that shouldn't be?)? What are the consequences?
    I would like to ask to this question: is there a testing procedure to figure out whether one has over-washed?

    And more generally speaking, besides the test of time and the HT-2, what tests are reliable indicators of a properly processed print?

    My own understanding so far would be that although there are theoretical guidelines regarding wash, mere conformity to these rules does not replace actual verification, and does not warrant by itself that a print or a film was properly processed, right? Somehow I think that people can get by with a as little theoretical knowledge as is needed to validate a bullet-proof testing.
    Using film since before it was hip.


    "One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11

    My APUG Portfolio

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