rapid, non-hardening alkaline fixer, questions on formulae

Discussion in 'Darkroom Developing and Printing' started by Shakti V. via PhotoKB.com, Oct 8, 2006.

  1. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    Attach or attack?
     
    Tom Phillips, Oct 24, 2006
    #41
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  2. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    What do you mean by "archival"?
     
    Tom Phillips, Oct 24, 2006
    #42
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  3. Shakti V. via PhotoKB.com

    Digitaltruth Guest

    As with any topic in photography, there are many theories and some
    people will swear by one method when others swear by another.
    Certainly, the fixation of film and paper can be carried out perfectly
    well with almost any fixer, regardless of whether it is acid or
    alkaline. The only real proof you can have of effectiveness is to carry
    out controlled tests on identical materials to determine any
    differences. Even such tests are subject to interpretation, as they
    cannot account for variables such as water qualities and age/quality of
    raw chemical compounds.

    We have performed chemical tests to determine accurate archival washing
    times for Clearfix Alkaline, and these times support the existing
    literature with regard to the speeds achievable by eliminating acid
    from the processing sequence. We have not done side-by-side testing
    with a commercial acid fixer, but I think it is safe to assume that
    times produced by Kodak/Ilford/Agfa/Fuji over the years have been
    carried out with a high degree of accuracy and that the much longer
    washing times required when using acid-based fixers are demonstrable in
    practice.

    Bill Troop's argument for the use of an all-alkaline processing
    sequence is not just about removal of hypo. There are a number of other
    points which Troop makes on page 106 of The Film Developing Cookbook
    which support his argument, notably the greater stability, capacity,
    permanence and protection of silver content.

    --Jon Mided

    Digitaltruth Photo
    http://www.digitaltruth.com
     
    Digitaltruth, Oct 24, 2006
    #43
  4. Shakti V. via PhotoKB.com

    Tom Phillips Guest


    Your reference link in this thread states the following:

    "Film processing...Films should be fixed for a minimum of
    twice the clearing time, or 2 to 5 minutes depending on
    the film and freshness of the fixer. When the film is
    sufficiently fixed, the fixer is drained and the film
    should be washed in fresh tap water for minimum of 3
    minutes..."

    Five minutes is the recommended wash time for Rapid
    Fix after HCA. So, 3 minutes v. 5 minutes? Hardly
    seems worth any debate ;)

    In any case I'd never wash my film for only 3 minutes
    regardless of tested efficacious (acid v. alkaline.)
    Washing for only the minimal time would seem a bit
    careless (and less archival), especially when it's no
    inconvenience at all to wash a few minutes longer.
    My bathroom break after developing/fixing is at least
    4 minutes :^)
     
    Tom Phillips, Oct 24, 2006
    #44
  5. Shakti V. via PhotoKB.com

    John Guest

    Do you still have the measurements ?

    ==
    John S. Douglas
    Photographer & Webmaster
    Legacy-photo.com - Xs750.net
     
    John, Oct 25, 2006
    #45
  6. Shakti V. via PhotoKB.com

    dan.c.quinn Guest

    An archival fix is one with a very low silver level per-unit
    volume of fixer. Ilford no longer does but did use the word archival.
    They specify a maximum of 0.5 grams of silver per liter working
    strength. Haist set a lower limit and did use the word archival.
    Assuming an average 0.08 grams silver per 8x10 and all that
    silver being left for the fix, worst case, the 1/4 liter of fix that
    I use per 8x10 will contain 0.32 grams of silver on a one
    liter basis. Well within Ilford's maximum.
    Ilford averages when they state that the capacity of one liter of
    working strength fix is ten 8x10s. Thay say as much. The same
    for the forty 8x10s at the commercial 2.0 grams per-liter. Dan
     
    dan.c.quinn, Oct 25, 2006
    #46
  7. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    Thanks, wasn't aware of the commercial data.
    However, I've never thought of fixer in terms
    of archival, only in terms of exhaustion (which
    I never allow to happen, discarding well before.)
    But I also don't use a one shot.

    Anyway think we had a similar fixer discussion in
    this nsg about a year ago. I was just confused by
    the commercial v. archival reference. But I might
    mention the silver load on the fixer will vary from
    print to print depending on how much halide in the
    emulsion remains after developing.
     
    Tom Phillips, Oct 25, 2006
    #47
  8. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    I still have the test strip and remember the
    measurements. I checked three areas based on
    my densitometer's ability to measure with a
    fair degree of accuracy (a 5mm reflection
    aperture): Highlight, a lower midtone area,
    and dense black. The orignal RDs after one
    minute in rapid fix 1:4 (my usual fix) were

    Highlight 0.14
    Midtone 1.00 to 1.05
    Black was about 2.00

    After 40 minutes of fixing the measured
    RDs varied by less than 0.05 for the mid
    tone and black areas and less than 0.01
    for the highlights. That was for a wet,
    unwashed and untoned strip. Note that I
    did not agitate, but just left the strip
    soaking in the fixer (hey, I had other
    things to do :) ). But given a certain +
    or - margin of error in measuring it
    appears there was no real change.

    Just dragged the test strip out of the
    trash and remeasured RDs. Very close to
    the same for highlight and midtone with
    slightly less RD for blacks (1.90.) Anyway
    I'd assume bleaching effects would vary
    from paper emulsion to paper emulsion and
    also assume any bleaching that does take
    place would be more pronounced in dense areas
    and less in highlights.

    Course, one empirical test isn't all that
    quantitative, but is still informative. I'll
    probably do some more in my next printing
    session 'cause now I'm curious...
     
    Tom Phillips, Oct 25, 2006
    #48
  9. Shakti V. via PhotoKB.com

    Digitaltruth Guest

    This is misleading as you are only quoting the time for fixation of
    film with a washing aid. I agree, that with these materials the time
    difference is small.

    However, when no washing aid is used, film can be fixed in Clearfix
    Alkaline for 2-5 minutes, and then washed in water for four minutes.
    That is a total minimum time of only 6 minutes! Kodak Rapid Fix, by
    comparison, specifies a fixing time of 2-4 minutes, followed by a
    washing time of 20-30 minutes if HCA is not used. That gives you a
    total minimum time of 22 minutes.

    If you don't use HCA, then the total time saved by using Clearfix
    Alkaline Fixer instead of Kodak Rapid Fixer would be 16-23 minutes.
    That is a huge difference.

    Similarly, washing times typically recommended for fiber-based paper
    are much longer when an acid fixer is used. Before they got out of the
    b&w paper business, Kodak recommended a washing time of at least one
    hour if no HCA was used, whereas with Clearfix Alkaline, you only need
    to wash for 20 minutes in the same circumstance. If a washing aid is
    used, or in the case of RC paper, the difference is much smaller.




    This is a common misconception, and I admit to having been guilty of it
    myself for many years. Your instinct that extra washing can only
    benefit the archival qualities of the print is intuitive, but may
    actually be wrong. While it might be a good idea to allow for some
    extra washing time to account for differences in water quality or
    circulation in your washing tank, you shouldn't overdo it. Published
    washing times normally include a built-in allowance for variations in
    water quality, so as long as you ensure that your film or paper are
    circulated reasonably well, there is no reason to exceed washing times.
    Your four minute bathroom break isn't going to be a problem, but if
    significantly longer times are used then you not only waste water, but
    you also increase the likelihood of the emulsion softening (and being
    more susceptible to scratches and damage). Additionally, its been known
    for many years that trace amounts of thiosulphate in the emulsion of
    paper actually act to protect the material and increase its archival
    qualities, so overwashing to the point that even these trace amounts of
    hypo are removed would decrease rather than increase the life
    expectancy of the material.

    I appreciate that alkaline fixation isn't for everyone, and that rapid
    acid fixers are perfectly suitable for all darkroom practices; however,
    if you try using an alkaline fixer and follow the guidelines
    accurately, I'd be surprised if you don't find it to be a better
    process overall. I never use a washing aid with film, so for me the
    speed difference is a big deal. When I use Clearfix Alkaline, I can
    process film in about half the time it used to take me with an acid
    fixer.

    --Jon Mided

    Digitaltruth Photo
    http://www.digitaltruth.com
     
    Digitaltruth, Oct 25, 2006
    #49
  10. Shakti V. via PhotoKB.com

    dan.c.quinn Guest

    Nice thing about the one-shot, very dilute, single bath,
    archival fix is that there is no doubt of having achieved an
    archival fix. Film or paper, archival results are automatic. In
    fact it is not possible to do less than archival.
    Of course dry or liquid, S or A, the thiosulfate must be in
    good condition. As a dry concentrate sodium thiosulfate has,
    I believe, a many many year stability. Dan
     
    dan.c.quinn, Oct 25, 2006
    #50
  11. Shakti V. via PhotoKB.com

    Tom Phillips Guest


    Well, I'm fairly confident my methods using rapid
    fix 1:4+HCA+wash produces archival results, at
    least as well as it can be defined. I'm sure your's
    do also. But the fact is just what constitutes an
    archival residue level of thiosulfate and products
    (to my knowledge) has yet to be defined. To me
    "archival" means processing to a known degree of
    certainty so the emulsion lasts as long as possible.
    Another good way to put it may be "beyond a
    reasonable doubt" since from all the literature
    I've read a "no doubt" or 100% degree of certainty
    is unattainable due to uncertainties as to just
    what constitutes archival.
     
    Tom Phillips, Oct 26, 2006
    #51
  12. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    Now you're being misleading. Why wouldn't I
    use HCA? I'd likely use it even with your fixer...
    Total time is then 9-12 minutes w/rapid fix (2-5
    minutes plus 2 minutes HCA plus 5 minutes wash.)
    Making an issue out of 5 minutes is entertaining
    but you also raise some other points below that
    are inaccurate...
    Depends. Using film strength fix for 30 sec.
    to one minute achieves complete fixing and
    reduces wash times to 10 minutes according to
    Ilford (again using HCA.) However, I never
    wash less fb prints than 20 minutes.

    Before they got out of the
    That's not what I said. I'm saying my
    instinct is minimal washing provides
    less assurance of adequate removal than
    washing a few minutes longer...

    While it might be a good idea to allow for some
    I seriously doubt with modern films softening
    of the emulsion is an issue. We're only talking
    about a few minutes difference in wash times
    and for me a few extra minutes provide assurance,
    while minimally washing provides little assurance
    in my mind...

    Additionally, its been known
    Not really. It's very difficult to completely
    remove residual thiosulfate and products. In
    other words achieving a zero level of residue
    is impossible (see Henry, 2nd ed. page 115.)
    Plus it's not defined exactly what level of
    residue constitutes "archival." So, the issue
    isn't wash time length, but washing enough (or
    otherwise using an archival procedure such as
    Ilford's) to achieve a sufficiently low level
    of residue...

    I really think this is a non-issue. For films the
    fix times remain similar. Wash times measured in
    minutes are fairly irrelevant and do not constitute
    "overwashing." I simply put my film in the washer
    and take it out when I'm ready and it's _convenient_
    for me (anywhere from 5 to 10 minutes.) Guess time
    just isn't as important for me (plus I'm not pushing
    a particular product or method.) I'd rather put my
    film/prints in the wash, then get a cup tea and take
    a relaxing break.
     
    Tom Phillips, Oct 26, 2006
    #52
  13. Shakti V. via PhotoKB.com

    Digitaltruth Guest

    Why wouldn't I use HCA? I'd likely use it even with your fixer...

    Tom, I appreciate that you use HCA and that the time difference isn't
    significant for you, but many other people do not choose to use a
    washing aid, in which case the time difference IS signficant. I don't
    use a washing aid with film because it is an extra and unnecessary
    step, and introduces the need to use an additional chemical during
    processing. With an acid fixer a washing aid can save you time, whereas
    with an alkaline fixer there is little benefit in using a washing aid
    for film.


    I stated in my previous post that the times with a washing aid were not
    significantly different for film or paper, although there is some time
    saving when using an alkaline fixer. You are again referring to times
    achievable only with a washing aid. I don't disagree with you about
    this, but there will be many other people who read this thread who do
    not use a washing aid. Ilford's recommended sequence makes use of their
    own washing aid which is not the same as HCA. As mentioned earlier, the
    time savings without the use of any washing aid is approximately 40
    minutes for fiber-based paper.


    I agree with this and follow a similar procedure myself. The only point
    I was trying to make is that it is not necessary to wash for additional
    time if correct procedures are followed.

    In principal I agree and certainly the risk may be very small if the
    additional time is only a few minutes; however, any additional wet time
    is undesirable as this is when the film is most susceptible to damage.
    The best practice is to shorten the wet time as much as possible to
    eliminate any extra risk. This is particulary important if unfiltered
    water is used as some particles can scratch the surface.



    I accept this point completely. All that I was suggesting is that as we
    do not know the exact level of residual thiosulfate which acts as a
    preservative, it is a good idea not to overwash materials by a
    signficant margin. Nonetheless, I think what you are saying is more
    accurate and that apart from time saving the major benefit of shortened
    washing times for FB paper is reduction in print curl as a result of
    shorter wet times.

    --Jon Mided

    Digitaltruth Photo
    http://www.digitaltruth.com
     
    Digitaltruth, Oct 26, 2006
    #53
  14. Digitaltruth a écrit :
    If main purpose is to save water, then a washaid + a low water
    consumption method (like the multiple changing water baths à la
    Ilford) is best.
    If you purpose is just to save some time, well, why not.
    For what I believe (I haven't done thorough tests myself), a washaid
    speeds up washing rate further than just keeping the pH neutral or
    slightly alkaline.
    I'm pretty sure to have seen tests that compared sodium sulfite versus
    carbonates (sodium/potassium) washaids that favored the sulfite.
    In Vestal's book there are several washing tests, I just don't recall
    if there is a comparison acid/washaid versus alkaline-only or
    alkaline/washaid. I'll check it this evening ...
    If you don't use a filtered water for washing you can already get
    particles on your neg during the first minute of washing. This is a
    very risky way to wash your negs.
    Of course, increasing the washing time will increase the risk of having
    such particles, but, without a serious filter, you're already living
    dangerously.
    Unless you know what the level of remaining thiosulfate is best and
    have a handy way to measure it for every print or neg, you may well
    remain before this optimal point which is much worse than going beyond
    that point.
    So, I definetely prefer to over-wash than under-wash ...

    Plus there are other more consistent ways to increase a print life
    through toning or additives like Sistan.
    Anyway, there is no need for a religious war on this subject, it's just
    a matter of preferences.

    I prefer to stop the activity of the developer quickly, the only way I
    know is to use a true stop bath. Then we're acid and a washaid bath is
    a good way to reduce both washing times and water consumption ...

    Finally, note that a washaid can be as simple as a 20grams/liter
    solution of sodium sulfite.
    It doesn't keep, so you have to dump it at the end of the session but
    its cost is ridiculous and very quick to prepare.


    Claudio Bonavolta
    http://www.bonavolta.ch
     
    Claudio Bonavolta, Oct 26, 2006
    #54
  15. Shakti V. via PhotoKB.com

    Lloyd Erlick Guest


    October 26, 2006, from Lloyd Erlick,

    Yes, exactly.

    Frankly, the imprecise and unscientific side
    of my mind blossoms under this sort of
    influence. (And that's a plus; you should
    hear Natalie's reaction to my overly finicky
    analyses and distinctions when they come up
    in real life, where they may be even less
    useful than in the darkroom...)

    I don't bother testing wash effectiveness
    after my all-alkaline film and/or paper
    processes. I'm glad to hear people say no
    washaid is necessary. Good. I'll just prepare
    my two percent sodium sulfite (ridiculously
    low price, eh?). I don't mind the couple of
    moments it takes to prepare (dissolves easily
    at room temperature, can't really call it
    work ... well, a container of water has to be
    filled, and a stirring rod turned, probably
    by hand ... oh, well). Belt and suspenders
    seems to suit me (at least in areas that can
    be called support or backup, such as
    developing the film correctly so we can get a
    nice picture that might even sell...)

    I like using bulk chemicals, especially for
    substances like sodium sulfite (and
    thiosulfate, for that matter), because they
    are really very cheap. A twenty five kilogram
    package of sodium sulfite anhydrous cost me
    sixty dollars. A liter of washaid uses one
    tablespoon of the stuff. Ridiculously cheap,
    yes, and it helps makes the whole endeavour
    quite possible to achieve.

    Please note I'm not saying scientific testing
    and analysis are not necessary or desirable.
    I'm happy to read reports by others and
    implement them as I see fit in my own
    practice.

    In the darkroom, all tests I've ever seen say
    that if we avoid overworking any given
    solution and provide enough or slightly 'too
    much' washing, everything will be OK.

    I like to know the number of 8x10s a liter of
    fix will fix, but not because I want to
    approach that limit too closely (and also not
    because I want to conduct tests to confirm
    the number in my own carkroom...). I just set
    my own limit at two-thirds the so-called
    limit, and take it on faith I have avoided
    overworking the solution.

    Most of my darkroom practices are more
    conservative than usual recommendations. Most
    of my effort in working out my system has
    been to find ways to implement those
    conservative practices in an easy and
    convenient way. I'm sure this has been true
    of most of us.

    If I tie a blindfold over my eyes before I
    start to develop a batch of film ... can I
    leave the lights on??

    regards,
    --le
    ________________________________
    Lloyd Erlick Portraits, Toronto.
    website: www.heylloyd.com
    telephone: 416-686-0326
    email:
    ________________________________
    --
     
    Lloyd Erlick, Oct 26, 2006
    #55
  16. Shakti V. via PhotoKB.com

    Lloyd Erlick Guest

    On 25 Oct 2006 14:44:11 -0700,

    October 26, 2006, from Lloyd Erlick,

    Yes, I've got a pail or two of the stuff I've
    been keeping since 1998. Sure seems unchanged
    to me.

    But I think that's actually pretty short
    term. Haven't we seen reports that people
    have used fifty year old hypo with normal
    results?

    It's funny; stuff that keeps nearly forever
    sells for C$1.30 a pound. But the little
    container of 250 grams (C$41!) of Glycin I
    bought in July (three-four months ago!) had
    to be used and used because by the end of it
    this month it was visibly deteriorating. At
    least thiosulfate is not wasted just by being
    stored.

    regards,
    --le
    ________________________________
    Lloyd Erlick Portraits, Toronto.
    website: www.heylloyd.com
    telephone: 416-686-0326
    email:
    ________________________________
    --
     
    Lloyd Erlick, Oct 26, 2006
    #56
  17. Shakti V. via PhotoKB.com

    Tom Phillips Guest

    FYI the use of salts in some form as an aid in washing
    has been known and practiced by photographers since
    at least the mid 19th century. Brine and even sea
    water were used (James, 4th ed. p. 454.) A wash aid
    is merely a 1-2% solution of sodium sulfite and the
    few minutes it takes to make and use it is hardly
    significant. It's effect on the efficaciousness of
    washing however IS very significant.

    Commercially packaged wash aids like Kodak HCA are
    chemically buffered to a neutral ph and also contain
    sodium metabisulfite, EDTA tetrasodium salt, and
    sodium citrate.
    You seem to insist on insinuating using wash aid
    is some great inconvenience when it's not....

    The real matter is most people who use an all
    alkaline process seem to do so because they
    have issues with acid fixers and stop baths.
    It's either irritating to them or don't like
    them for other reasons. Either method can
    produce desired archival results, but I seriously
    doubt most use an alkaline fix to save a mere 5
    minutes in the darkroom...

    I don't disagree with you about
    Must be why packaged wash aids are so common and
    sell so well?
    Makes little difference. The effect of the sulfite
    is to aid in the removal of thiosulfate byproducts. As
    noted in James a very wide range of salts can do this,
    including sea water.

    As mentioned earlier, the
    Certainly time is a marketing point for your clearfix,
    except similar wash time savings are achievable using
    any brand of HCA...

    snip...
    Well, what you said was "overwashing to the
    point that even these trace amounts of hypo
    are removed..." In fact, you cannot remove
    what you are calling "trace amounts" through
    washing. Not even after 2 days of washing (Henry.)


    Nonetheless, I think what you are saying is more
    Print curl has nothing to do with the
    length of the wash time.
     
    Tom Phillips, Oct 26, 2006
    #57
  18. Shakti V. via PhotoKB.com

    dan.c.quinn Guest

    So, what happened to the two percent sodium carbonate?
    Agfa's recommended hca for many years and the one yourself
    used for many years? Dan
     
    dan.c.quinn, Oct 26, 2006
    #58
  19. Shakti V. via PhotoKB.com

    dan.c.quinn Guest

    IIRC it was found in the 1840s that prints fixed
    in thiosulfate lasted longer. Concerns over print longevity
    have existed since the first photgraph was taken. What
    today constitutes an archival processing was likely
    well established by the 1880s or 90s.
    I rather think, as you've mentioned an hca of some sort
    was likely included here and there. I'm sure photographers
    150 years ago took their work seriously and worked even
    then toward archival results. I've no doubt there exists in
    long ago journals much evidence. Dan
     
    dan.c.quinn, Oct 26, 2006
    #59
  20. Shakti V. via PhotoKB.com

    Tom Phillips Guest


    I think that's correct about the date for using
    thiosulfate. According to Rosenblum's World History
    of Photography Sir John Herschel discovered its
    fixing properties as early as 1819 but for some
    reason didn't inform photographers about it until
    1839, when both Louis Daguerre and Henry Fox Talbot
    stopped using sodium chloride and switched to "hypo."

    Also correct about collodian photographers, who
    were particularly careful about processing, wanting
    their prints to last as long as possible. So I would
    say archival processing dates earlier than that,
    though I don't know if they called it "archival."
    According to Rosenblum, committees were set up to
    study and identify various causes of print fading
    as early as the 1850's. Inadequate washing and
    fixing were among the discovered causes...
     
    Tom Phillips, Oct 27, 2006
    #60
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