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  1. #101

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    Quote Originally Posted by dancqu View Post
    Well Now! An opportunity for Mr. Troop to toot HIS
    own horn for a change. Perhaps a list of Journals of
    this and that Society in which his findings have been
    published.

    For myself I tire of the endless applauding and leaning
    upon of such as Levinson and Haist who finished their
    work 40 and even 50 years ago. Dan
    PS: Levinson or Levenson? Depends upon whom you
    are reading, Ron or Bill.

  2. #102

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    Quote Originally Posted by dancqu View Post
    PS: Levinson or Levenson? Depends upon whom you
    are reading, Ron or Bill.
    I found misspelling in your post; both Ron Mowrey and Bill Troop are in my ignore list and I don't read their posts. If they repeat misspelling of Levenson, you might want to remind them and also question their knowledge of his work.

  3. #103
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    There are both a G. Levinson and a G. Levenson who are cited in photographic textbooks. G. Levinson is the less prominent of the two. G. I. P. Levenson has been cited to assist in separating the two.

    I have not checked my posts, but I'm sorry if I misspelled his last name as Levinson in error in this context. It is correctly G. I. P. Levenson. Please excuse the error, but under the circumstances with the great similarity, I hope you excuse the 'crossover'. It was certainly unintentional.

    PE

  4. #104
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    Quote Originally Posted by billtroop View Post
    the book I originally wrote was about five times longer (no exaggeration) and would have been unpublishable in the late 90s. My question is, what is publishable today?
    Bill, if you publish it, I will buy it! Website, PDF, paper, whatever. The sheer delight of solid and synthetized information is a constant joy. I wish I'll have enough spare money some day to buy the updated version of Mr Haist's book, but for now I make do with a library copy.
    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

  5. #105
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    Michel;

    The updated version was never published. Work was interrupted as noted above. C'est dommage.

    PE

  6. #106

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    "I found misspelling in your post; both Ron Mowrey and Bill Troop are in my ignore list and I don't read their posts."

    "You don't seem to know how rude you are." (Goethe) (who also used variant spellings!)

    Re the Ilford system, Roger, I don't have the Kodak table handy but it's buried in Haist and runs something like this. In a continuous stream of water wash, for film processed in an alkaline fixer, archival levels of hypo may be reached in something like five seconds, but residual hydroquinone will take 45 seconds to remove. (The reference may be in my book. If not, it should be.)

    This astonishing finding suggests that for an alkaline or near-neutral fixer, the important thing to test for, as regards film, may not be residual hypo but residual HQ/other. Haist could not be explicit about any of this because too much of it fell into the trade secret area. We all have to remember that Kodak aggressively supervised his book. Except for the utmost generality, he was not permitted to make any statement that had not previously been published in the literature. He also wasn't permitted to connect dots which would have made life much easier for future generations of readers

    So, again, I'm not entirely surprised if, under some circumstances, an acid fixer (perhaps closer to neutral than not) will give an acceptable wash under some circumstances, with 5-6 quick changes of water.

    Those circumstances would have to include excellent condition of the fixer, perfect technique and timing, and a given film emulsion, for whereas it may work with some films, it can't be expected to work with all.

    But that still doesn't take into account other residua from the development process which could be damaging.

    So now you have to look at what is happening before the fixer step and after developing.

    Will there be a stop bath? Will there be a continuous or stationary water rinse? Or will the film be plunged direct into the fixer?

    There are all kinds of possibilities for nastiness if there is enough residual developer in the film to be active in the fixer. Dichroic or other fog could result.

    So I would be uncomfortable recommending any processing sequence that did not include either (a) at least sixty seconds in a fresh stop bath with continuous agitation, or (b) a continuous water rinse of two minutes or (c) a highly buffered, exceptionally well-preserved acid fixer. Two minutes sounds a lot but it includes a safety factor that is particularly applicable to alkaline fixing because we need to avoid developer activity in the fixer.

    I particularly warn against the error, perpetuated by the marvellously bright if obstreperously self-destructive graduate student (to use a style of soubriquet from the Meian era which he will appreciate), of confirming the Ilford method without replicating the chemistry, and that under a wide variety of processing conditions.

    It is always possible in photography to make an experimental conclusion that applies in a particular set of circumstances. So if you are an expert as you obviously are, and you find that a particular technique works, I accept that. But I can't accept that as a general recommendation, because when I make a recommendation, it has to be proof against an enormous number of circumstances I can't foresee.

    I am grateful to you for forcing me to think this out more rigorously, even if my opinion hasn't yet changed!

    My final caution: virtually all after-market rapid fixers are sold with an optional hardener, or were originally sold with such an optional hardener. This means their pH must be relatively acid. Ilford's non-hardening fixers don't suffer from this requirement; therefore the pH could be higher (not neutral or alkaline, but moving up on the scale) and therefore would wash out of film perceptibly quicker. For this reason, in any rapid wash sequence, you have to know the pH of the fixer as prepared and as used. What works with Ilford fixer A won't necessarily work with Kodak fixer B.

    With all of this, I think we are beginning to approach conditions where very rapid washing of film is sometimes possible with small amounts of water. But I can't let go of the idea that this can only be true under certain carefully defined conditions, and should not be disseminated as general rules of everyday technique.

  7. #107

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    Dear Bill,

    I should like to thank you too, as I shall in future add the further caveat that while I recommend the Ilford wash sequence unreservedly, on the base of my own tests and those of others, I have not tested it with many fixers and that I can only verify it from personal experience with Ilford and Tetenal fixers. I may or may not add that others have found that it works with other fixers: this addition will depend (as we are both very aware) on the space available. I shall of course continue to state that this wash sequence applies only to non-hardening fixers.

    I would also point out that I have almost always said that (like others) I find it almost impossible to believe that the Ilford sequence works, and that (like others) I normally repeat one step, or let it sit for a little while in the distilled water after the triple set of inversions -- except, of course, when I am planning on running a test afterwards...

    Cheers,

    R.

  8. #108
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    Quote Originally Posted by Roger Hicks View Post
    I would also point out that I have almost always said that (like others) I find it almost impossible to believe that the Ilford sequence works, and that (like others) I normally repeat one step, or let it sit for a little while in the distilled water after the triple set of inversions.

    I also do this whilst not quite believing that such a simple sequence will work.

    In reality, Ilford will have put in a safety margin so in ideal conditions, 75% or perhaps even 50% of their reccomended wash sequence would probably be o.k.

    Steve.

  9. #109
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    As an added thought on hydroquinone retention, it is known that hydroquinone itself does not diffuse rapidly and is rather insoluable at an acid pH. It forms a sodium salt or ammonium salt at alkaline pH values. Grant and I know this and so the conditions for wash on the alkaline side are best for removing excess HQ. Bill knew this as well I think, as we see.

    OTOH, color developers and some B&W developers are amines or contain amino groups which are more soluable on the acid side, and therefore Metol and the p-phenylene diamines are more soluable on the acid side.

    This interesting dilemma was solved at EK when we decided to use the near neutral fix and blix which gave us the best of both worlds. In addition, adding swelling agents and taking advantage of synergy in fixing can speed both fixing and washing at whatever pH. I have done extensive experiments on this with Keith Stephen, and he had developed a whole family of organics and inorganics that accelerated fixing. This latter is never discussed on the internet to any extent, and is rarely used in products sold.

    One of these low toxicity ingredients is now sold by several chemical companies, but is so expensive (IDK why though, it is easy to make), so if I can get some I can whip up a super fix that would knock your socks off! No, I won't give you the name. I'm trying to get some myself. Right now, I cannot afford the minimum order.

    I may discuss this phenomenon at a later date. Our erstwhile graduate student seems to be totally oblivious to this type of fix in spite of all of his studies. And yet, it is patented by a number of individuals and is written up in Haist and Mees (although disguised ) somewhat to protect outright disclosure.

    Just as a caution, one popular fixer out there is so poor that, it spoiled on my shelf before I could get to test it, so beware... Not all fixers are made up to Kodak or Ilford standards. My bottle of test fixes are on a shelf here, and this one spoiled while the Kodak fixer, TF-4 and my Super Fix are still just fine.

    PE

  10. #110
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    I just noticed in reviewing this thread that my name was taken in vain. I mean that literally. Very little of my practical work has been done with expectations of long life. Strangely, a lot of it has survived at least 30 years with no sign of degradation. I took many photos between 1960 and 1980 of visiting musical artists while I was principle oboist with the Peninsula Symphony of Newport News and the Norfolk Symphony of Virginia and they are still in excellent condition. This was done while the bathroom was "bath by appointment only." I was in a hurry to get the photos processed between dress rehearsal when I took them and the concert the next day, with a full day's work at NASA between. I wanted to present copies to the guest artist and get one autographed for myself. Alicia De Larrocha, Claudio Arrau, Jorje Bolet (also an avid photographer), Vladimir Ashkenazy and many others are among them.

    I have a collection of glass plate negatives that my grandfather took before 1905 that were stored (not preserved) in brown paper envelopes in an attic in West Virginia. The ones that are not in good condition are so because of humidity. The envelopes are what librarians refer to as "cornflakes" of which some are embedded in the gelatine. I have no idea what procedure he used in washing.

    I am not about to preach to anyone my technique, which was about 1% good planning and 99% good luck. I am an engineer by nature, which only means that when I have an engineering problem before me, I read books and write equations and do whatever else is necessary to find a solution. I had occasion while employed by NASA to solve problems in aerodynamics, electronics, photography, human factors and some I don't remember. I took one of my instructors at WVU literally when he said "Engineers can do anything." That was about 60 years ago.
    Gadget Gainer



 

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