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  1. #11

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    My impression is that color dyes are inherently unstable and will fade eventually, and virtually all color images are based on dyes. I am not stating this as fact, just my impression. Like all artifical red food dyes are carcinogenic--an impression I have, not a fact. Some physical characteristics of a substance go hand-in-hand with other characteristics--you can't have one without the other.

    Ultraviolet light, of course, is the enemy of any color image.

    Black & white silver (or other metal based) images are probably the most permanent images we can make if properly processed. There are photos over 100 years old that are still fine, and some of the prints I made in the 1960's when I started processing black & white are still fine--I knew nothing of "archival" back then, I just fixed and washed the prints properly.

    I think that the black & white silver-based image is one of the reasons I believe black & white silver-based photography will be with us for a long time to come.

    Charlie Strack

  2. #12
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    Free radicals are the problem with dyes. Free radical chain stoppers fix the problem to a great extent. Therefore, a dye stabilized with such an agent (a Vitamin E derivative usually) will stop UV and O3 fade. Also, use of UV absorbers will help fix the UV problem.

    As for carcenogenicity, your impression is wrong. If it were, we would be dying a lot more rapidly of cancers. Azo dyes and the like are quite prevalent everywhere.

    I would be much much more concerned about charcoal grilled meats and cigarette smoke which contain up to hundreds of carcinogens!

    PE

  3. #13

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    Quote Originally Posted by Photo Engineer View Post
    I would be much much more concerned about charcoal grilled meats and cigarette smoke which contain up to hundreds of carcinogens!

    PE
    You mean BBQ is bad for you? Who knew?
    Bruce Watson
    AchromaticArts.com

  4. #14
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    Actually, this is true. There are many harmful carcinogens generated by Charcoal, by the lighter fluid and by the burning or charring of the meat by the intense heat.

    These produce a number of carcinogens. I cannot locate any specific papers at this time, but there was considerable uproar about this 10 years ago or thereabouts.

    PE

  5. #15
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    Who knows about RC? I, myself, would never consider it for serious work I wish to last.
    I know that FB is supposed to last longer but I don't work with it now because I really don't have the facilities. I don't have running water in my darkroom and nowhere to leave prints washing or drying. I guess I don't do anything very seriously now, but I wish RC wasn't a second-rate technology.
    f/22 and be there.

  6. #16
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    There is no proof either way, under real conditions, that today's RC is better or worse than FB. The tests are all simulations so far, as RC is not "old" enough.

    PE

  7. #17
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    Well there's that, but not only that, I've heard one member on here saying that he had some Foma RC paper (which is what I use right now) "silver out" in as little as a few years. I'm not sure what that looks like but it's pretty worrying.
    f/22 and be there.

  8. #18

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    Quote Originally Posted by BetterSense View Post
    I don't mean to sound pessimistic, but since beginning to pay attention to such things, I've come to notice just how often and how badly color prints fade. It seems that a good many, possibly the majority of color prints I see hanging in businesses are faded, usually noticeably, and sometimes conspicuously, usually to an ugly blue.
    There's a misconception that what fades prints is UV light. While UV does damage photographic prints, so does visible light. And most businesses are lit beyond all reason.

    Next, the air in most businesses tends to be fairly polluted. This is especially true if it's a food business. Cooking releases all kinds of stuff into the atmosphere. Hardly any of this is good for photographic prints. Ozone in particular will rip into a dye molecule with gusto. So don't hang your prints over the office copier, a notorious Ozone emitter. Or near your electrostatic air cleaner.

    Quote Originally Posted by BetterSense View Post
    Just last week a saw color prints in a research company (the prints were probably 30+ years old), an Arbys (surely not more than 15), a donut shop (wouldn't surprise me if they were 50), and at a University (definitely not more than 10), that all were faded to a blue tint. All were displayed in moderate lighting, to be fair. This makes me pessimistic about working in color and getting common minilab or lightjett'd color prints.
    You'll get over your pessimism. At least I got over mine.

    Quote Originally Posted by BetterSense View Post
    Is this because these are all cheap prints, or do all color prints do this? I know there is Cibachrome, which I doubt I have ever seen, but what about other processes?. I hear that B&W fiber-based prints should last 100+ years, nobody knows how long B&W RC prints last, but I don't really know about the archival properties of color chemistries or of inkjet printing.
    Cheap? No. Dye-based, yes. We probably already have silver gelatin prints that have lasted longer than 100 years (silver gelatin was introduced about 1910 IIRC), I would expect a properly processed and stored silver gelatin print to last about as long as the paper substrate can hold it. Color prints are another story.

    Since you brought up inkjet (it wasn't me, don't blame me, I'm merely responding here), I have to say that pigment inks are perhaps the most long lived of the color processes. I'm thinking that there's a color carbon process that's also pigment, so it's not just inkjets.

    But the pigment inks for inkjets are really less than two decades old. And changing rapidly. It's difficult to get a handle on exactly what they'll do over time.

    To that end, there's ongoing research. Look at CoOL at Stanford, Wilhelm, and a guy in Maryland who's name I can't remember right off who's actually doing testing correctly -- getting fade and delta-e both for all the inks and inks in combination, and older photographic print processes too like RA-4 (at least I seem to recall that he's going to be testing RA-4 and some other processes to get comparisons). A lot of people in the industry think he's got his act together. If I can find his URL I'll append it when I find it -- he's the most interesting of the lot IMHO.
    Bruce Watson
    AchromaticArts.com

  9. #19
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    Quote Originally Posted by Photo Engineer View Post
    Actually, this is true. There are many harmful carcinogens generated by Charcoal, by the lighter fluid and by the burning or charring of the meat by the intense heat.

    These produce a number of carcinogens. I cannot locate any specific papers at this time, but there was considerable uproar about this 10 years ago or thereabouts.

    PE
    That's one of those things where you say oh well and continue doing it. That and RA4 printing.

    It's like a race towards death. Which will happen first? Will the image fade or the RC substrate decay into goo? It's like the race of the tortoise and the tortoise with the maimed broken leg.

    Well, I made some RA4 prints way back when I was 15 in 2008 and they haven't faded a bit as far as I can tell. I guess the color was bad to begin with, but that's another issue.
    Last edited by tiberiustibz; 05-29-2009 at 08:42 PM. Click to view previous post history.

  10. #20

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    Quote Originally Posted by Photo Engineer View Post
    Actually, this is true. There are many harmful carcinogens generated by Charcoal, by the lighter fluid and by the burning or charring of the meat by the intense heat.

    These produce a number of carcinogens. I cannot locate any specific papers at this time, but there was considerable uproar about this 10 years ago or thereabouts.

    PE
    I know it's true. I was just pulling your leg. I even put in a winky face to show that!

    On the serious side, not only is grilling meat dangerous from the standpoint of the carcinogens, but also from many other standpoints. A pound of meat on the plate ready to eat is about equal to a pound of Middle Eastern oil. It costs not just transportation oil, but the making of fertilizers, pesticides, the antibiotics and growth hormones they pump into the animals (that you eat, all of which come from oil and natural gas), the styrofoam plate and the plastic wrap the butcher uses, all that. Meat is a surprisingly large contributor to global warming.

    Since I found this out I eat a lot less meat than I used to. Sigh...
    Bruce Watson
    AchromaticArts.com

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