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  1. #11
    Photo Engineer's Avatar
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    The silver content of emulsions coated on baryta vs RC was identical, as was gelatin level, but the addenda was varied to allow for the absorption of the addenda by the permeable baryta. Generally, keeping was far better on the RC and the same was true for B&W. The surfactant and water content was different due to the different properties of the two supports.

    The Type II stabilzer first used AEH, a type of sugar (a hepitatol), but this was found to be too variable, so it was changed to sorbitol. The sorbitol and the AEH increased the glass transition temperature of the gelatin and thereby provided a rather impermeable oxygen barrier. It made the prints stickier in humid environments too, and so it was recommended only for enlargements that were to be mounted not prints being stacked.

    The type II stabilizer was also at a different pH than the normal stabilzer. They were both discontinued with the Ektaprint 2 process. At that time though, AFAIK, the sorbitol could double the light stability of any paper regardless of whether the antioxidant was incorporated or not. It even improved the stability of couplers that made dispersions with high glass transition temperatures (again see Tuite et al).

    Photofinishers and professionals didn't want to work with the Type II stabilzer.

    This work was published by Edens AFAIK. It was also discussed by Tuite in a presentation at the SPSE conference in Washington DC in 1988 (IIRC), where Henry Wilhelm gave his first presentation.

    The only other recent references are the book by Jon Kapecki used as a text in the ICIS course and the presentations by Kodak and Fuji. That book probably does not mention the Type II stabilizer though. I forget offhand.

    PE

  2. #12

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    Well, I'll just hope for the manufacturers of inkjet papers to come up with a product that matches the look of an air-dried glossy baryta surface. What I've seen so far wasn't that impressive.
    Be careful his bow tie is really a camera
    timeUnit

  3. #13
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    Glossy Baryta was not intended to be truly glossy unless it was ferrotyped. I see ferrotyping as a lost art, but a properly ferrotyped Baryta B&W or color print will blow away an air dried glossy print any day.

    PE

  4. #14
    Joe VanCleave's Avatar
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    Whose Paper Are We Talking About?

    Quote Originally Posted by Photo Engineer View Post
    ...Current images from color RC papers are expected to last from 100 to 200 years depending on the keeping conditions and manufacturer. This has been achieved during the last 10 years or so, although overall image stability has been improving constantly for the last 50 - 60 years since the introduction of the first color imaging materials....

    PE

    Not to be argumentative (although I suppose posting a reply is intrinsically just that), but which current manufacturer of RC paper are you referring to? Is this reflective of your experience solely at EK, or does this statement universally apply, industry-wide across the board, to any RC paper I may choose to purchase in December of 2006?

    Since you stated that it depends, in part, on the manufacturer, can you be more specific, so as to help us laymen in making better decisions on purchasing RC paper? What about the easten European brands of B/W RC paper; do you hold the same degree of confidence as you do with the products no longer manufactured by EK?

    I suppose you can sense the frustration of, after eagerly lending an ear to the wisdom and sage advice of experts, to find their statements mostly opinion, with little of substance.

    How is this thread supposed to bolster our decision-making regarding the longevity of RC vs fiber paper? Granted, the context of this thread is about which papers to use for hand-coating, which is not in my foreseeable future, but the discussion seems to be relevant to commercially manufactured papers as well.

    Where do us laymen (and potential customers, the only ones who will keep this technology alive in the marketplace) find authoritative information on the keeping properties of such materials? Most manufacturers' websites give information, if at all, that reads more like a legal disclaimer than a statement of expected product performance.

    I may also state here that, as a qualified neophyte, the academic and arcane arguments between you and Ryuji seem to me to be nothing more than a battle of two egos. While it provides for some degree of entertainment in my otherwise miserable life, I am beginning to question the advocacy of relying solely on self-proclaimed 'experts'.

    I appreciate the candid and otherwise priceless wisdom that is (occasionally) dispensed here. And the historical lessons on the engineering developments of modern photographic materials are of academic interest to some. All the rest is chaff.

    There's nothing that beats experience; especially one's own!

  5. #15
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    Quote Originally Posted by Joe VanCleave View Post
    Not to be argumentative (although I suppose posting a reply is intrinsically just that), but which current manufacturer of RC paper are you referring to? Is this reflective of your experience solely at EK, or does this statement universally apply, industry-wide across the board, to any RC paper I may choose to purchase in December of 2006?

    Since you stated that it depends, in part, on the manufacturer, can you be more specific, so as to help us laymen in making better decisions on purchasing RC paper? What about the easten European brands of B/W RC paper; do you hold the same degree of confidence as you do with the products no longer manufactured by EK?

    I suppose you can sense the frustration of, after eagerly lending an ear to the wisdom and sage advice of experts, to find their statements mostly opinion, with little of substance.

    How is this thread supposed to bolster our decision-making regarding the longevity of RC vs fiber paper? Granted, the context of this thread is about which papers to use for hand-coating, which is not in my foreseeable future, but the discussion seems to be relevant to commercially manufactured papers as well.

    Where do us laymen (and potential customers, the only ones who will keep this technology alive in the marketplace) find authoritative information on the keeping properties of such materials? Most manufacturers' websites give information, if at all, that reads more like a legal disclaimer than a statement of expected product performance.

    I may also state here that, as a qualified neophyte, the academic and arcane arguments between you and Ryuji seem to me to be nothing more than a battle of two egos. While it provides for some degree of entertainment in my otherwise miserable life, I am beginning to question the advocacy of relying solely on self-proclaimed 'experts'.

    I appreciate the candid and otherwise priceless wisdom that is (occasionally) dispensed here. And the historical lessons on the engineering developments of modern photographic materials are of academic interest to some. All the rest is chaff.

    There's nothing that beats experience; especially one's own!
    Joe;

    I don't take it as argumentative.

    My statement about the life of a color photographic material is based on several things. First, there is a statement on Kodak's web site regarding the longevity of Kodak Endura paper. Second, Fuji has made a similar statement to the photo industry. Third, Henry Wilhelm discussed this with me personally and his institute has published data on longevity. Fourth, the Image Stability lab at RIT is in general agreement with this data. Fifth, I took the ICIS course on image stability in May. And, last but not least is my more than 30 years experience as an engineer at Kodak, with about 1/2 of that time being involved in some way with image stability.

    Now, the disagreement in value centers around the testing method. You get different results with each paper depending on how you test it. And, the ANSI committee on image permanence has yet to make a definitive statement on this subject with definitive standards, so each lab makes its own standard.

    Nowhere in this thread was handcoating discussed that I know of. This was solely a discussion about manufacturing color products. They cannot be easily hand coated, although I have done it. It is truly a pain, and very expensive due to the chemistry and equipment needed.

    I do not wish to have an argument with Ryuji. I merely state facts from my actual hands-on experience along side his observations from the literature. Sometimes they agree and sometimes they don't agree. This is often the nature of printed material vs hands-on in engineering and should not reflect badly in any way on either of us.

    PE

  6. #16

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    Quote Originally Posted by Photo Engineer View Post
    Now, the disagreement in value centers around the testing method. You get different results with each paper depending on how you test it. And, the ANSI committee on image permanence has yet to make a definitive statement on this subject with definitive standards, so each lab makes its own standard.
    As I see it, Joe is more interested in comparing the longevity of images produced with different paper products. There is clear difference between products here. But Joe may want to pay attention to the different test methods used by different manufacturers. Eastman Kodak uses different condition and calculation method to come up with the number of years their color prints will last in display condition. Most other companies (both RA-4 type paper manufacturers and inkjet printer manufacturers) use more severe testing condition and more conservative projection method. What it means is that if the number is the same, it means Kodak prints go before other prints.

    Another thing the consumers can consult is guidelines made for museum conservators. They consider RA-4 type prints "unstable" and the guideline recommends limited brightness of viewing light during display, and humidity-controlled refrigeration during storage. B&W materials are quite a bit more durable than dye-based color images, although some manufacturers (I won't say who, since Ron will go on forever if I do---maybe he will anyway, even if I don't) have better dyes and dye couplers than others. There are several books written on this topic, and there are at least a few if you count English language only. They are written for museum conservators, conservation scientists and technical staff so they are more accessible than papers published on journals, though you often need to consult the latter for more details.

    About the permanence of eastern/central european RC stock, I don't think anyone knowledgeable ion the subject makes a serious comment. RC paper production had several technical pitfalls that Kodak, AGFA, Fujifilm and Ilford got stuck several times. All of the problems are documented in various places, and you know what they are even if you are not an industrial spy. But figuring out how to iron out all the problems is not that easy... I'd definitely stick with products from above 4 until someone does thorough testing on others' products... but I am not hopeful that anyone will do such a task in this market situation.
    Last edited by Ryuji; 01-08-2007 at 12:24 AM. Click to view previous post history.

  7. #17

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    Quote Originally Posted by Photo Engineer View Post
    The Type II stabilzer first used AEH, a type of sugar (a hepitatol), but this was found to be too variable, so it was changed to sorbitol. The sorbitol and the AEH increased the glass transition temperature of the gelatin and thereby provided a rather impermeable oxygen barrier. It made the prints stickier in humid environments too, and so it was recommended only for enlargements that were to be mounted not prints being stacked.
    I'm not sure about that explanation. Glass transition temperature of gelatin is only lowered by adding small amount of sorbitol. Plus, I did this experiment myself some time ago and srbitol-treated gelatin is permeable to oxygen and peroxide. If sorbitol treatment indeed prolonged the image longevity I suspect it did so via radical scavenging action on excited dye molecues, or perhaps by scavenging the offending molecule or its intermediate forms.

  8. #18
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    I have a proposition to make :

    Print one negative on different colour papers (Fuji, Kodak, Eastern ones etc) and send them to me. I will place them on a rooftop in the center of Athens. They'll get 300 days of sunshine/year, pollution (NO's, SO's, Benzolium, heavy metals, CO etc etc) and acid rain (when it rains, that is rarely). In one years time, I bet most of them will have "gone"... we can then compare them to see who'll be the winner (if we can clean them of the filth that'll have been deposited on them).

    The processing of the prints has to be the same, so it has to be ONE of you who'll print and process in the same RA4 machine at the same time.

  9. #19

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    Before doing such a test, you might want to consult Wilhelm's website. He has done light fading tests on a few common RA-4 papers.

  10. #20
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    I think it fair to comment on the reported view of one museum curator given me second hand. He felt that digital color prints were archival. Well, so much for that.

    Opinion is opinion, but sometimes even well meaning tests are not very good or very revealing. Kodak, Fuji and Wilhelm differ greatly in the results of their tests. And, you must remember that not one of them is truly objective.

    If they were, then where is image smear publicly reported as part of the continuing comparisions of digital vs analog, and where is the reporting of RC support stability itself? These are two big issues not being properly disseminated. These issues have been tested by all manufacturers and by Wilhelm, but are not front page issues.

    PE

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