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  1. #21
    Marco B's Avatar
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    Quote Originally Posted by Loris Medici View Post
    I've made my points very clearly. Relax and print / do your art Marco, don't be so anal, OK?
    One last remark:

    Loris, you were the last person I would have expected to call me "anal" about this kind of stuff...

    From all your regular posts here on APUG and Hybridphoto, I have the strong feeling you, just like me, are a person who devours anything or any form of (scientific) literature related to photography and alternative processes...

    You even contacted Mike Ware himself directly in 2006 to discuss the longevity of his Argyrotype process versus Van Dyke Brown, a discussion topic on another forum you hadn't even started yourself! :o

    Now who is "the anal person" here??? (I think we both are...)
    Last edited by Marco B; 06-05-2010 at 06:25 AM. Click to view previous post history.
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    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  2. #22

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    Are some of the issues with Platinotype more of historical/conservator interest in that current, recommended methods to not include hydrochloric acid as clearing bath?
    Is the catalytic properties of Palladium more of an issue at higher temperatures normally not found in print archives?
    Does the recommendation for acidifying some papers for pt/pd usage actually lead to deterioration of the paper?
    van Huyck Photo
    "Progress is only a direction, and it's often the wrong direction"

  3. #23
    Marco B's Avatar
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    Quote Originally Posted by doughowk View Post
    Are some of the issues with Platinotype more of historical/conservator interest in that current, recommended methods to not include hydrochloric acid as clearing bath?
    Is the catalytic properties of Palladium more of an issue at higher temperatures normally not found in print archives?
    Does the recommendation for acidifying some papers for pt/pd usage actually lead to deterioration of the paper?
    Doug, all good questions!! Those are the ones I would like to have discussed and maybe even answered here in this thread... that's why I started it.
    My website

    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  4. #24

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    Quote Originally Posted by Marco B View Post
    ...

    So, if people feel the need to discuss and argue the longevity of silver gelatine prints, why on earth not discuss or argue the possible issues with other print types like Pt/Pd???

    I just don't get it... I also have the slight feeling that Pt/Pd printers, simply "don't want to hear it"... they invested time and money to get the longest longevity prints, and now someone is telling them there might (!) be issues in some cases they had not foreseen...
    Hi Marco,

    I don't say lets not discuss it exactly, but (I think) it's pretty much useless for us photogs and/or collectors. I mean the possible negative effects showing up (if any) will take at least 4-5 generations of both groups. It's more a conservators' issue and this isn't a conservation list/forum...

    Also as a practitioner of the medium (not current - but I was doing a lot of pt/pd few years ago. I just dumped it because my attention / interest just turned into pigment processes. Now I'm only thinking about pt/pd in the context where I'm also going to put some gum layers on top of it...), I confidently can say that my interest in pt/pd wasn't - a little bit - related to the longevity of the process, and I'm sure it's not at the top of the list of priorities of any other practitioner or master too. (It's important, no one will deny that, though.) It's all (well, maybe more) about the (unequaled) wonderful tones and smoothness we're able to get with the process... (+ handmade/tactile qualities + freedom of choosing / matching substrate to subject + image in / integrated to the substrate, not on top of it / separated + ... and so on...) Edit: You have to do few to understand that...

    Quote Originally Posted by Marco B View Post
    ...

    Mike Ware is "not just everybody", he seems quite well respected, and undoubtedly has made some significant contributions to the alternative process community. Why would he risk his reputation telling nonsense about Pt/Pd? So if he says there have been documented cases of issues with Pt/Pd due to acidification, I do think this is something to listen to and possibly learn from.
    I have great respect for Mike Ware and admire him. I'm not saying he's telling nonsense (that's something impossible in my experience), everything he thinks and tells is very important to me. See the first paragraph for my (seemingly) bitter approach to the subject...

    Regards,
    Loris.
    Last edited by Loris Medici; 06-05-2010 at 01:46 PM. Click to view previous post history. Reason: Added a small remark and changed a sentence for clarification...

  5. #25
    Marco B's Avatar
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    Quote Originally Posted by Loris Medici View Post
    Hi Marco,

    I don't say lets not discuss it exactly, but (I think) it's pretty much useless for us photogs and/or collectors. I mean the possible negative effects showing up (if any) will take at least 4-5 generations of both groups. It's more a conservators' issue and this isn't a conservation list/forum... Loris.
    Loris,

    Thanks for taking the time to explain yourself a bit further. Don't get me wrong, my intention was by no means to withhold anyone from practising the beautiful art of Pt/Pd printing (for whatever reason they may desire it, whether aesthetics, archivability or any other reason), by scaring them with stories about issues with longevity, but merely to inform and learn more.

    However, I do not subscribe to the notion that this belong on a specialized conservation forum... APUG is just a "general" photography forum. All kinds of subjects are discussed here, and the longevity of silver gelatine prints is one of the topics that comes up on a very regular basis, and I think not without reason. So, personally, I see absolutely no reason not to discuss the longevity and conservation topics related to any other photographic process. It belongs on APUG as well.

    Marco
    My website

    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  6. #26
    Marco B's Avatar
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    Well, OK, I know hit on a very interesting article by Adam Gottlieb, available online discussing the:

    "CHEMISTRY AND CONSERVATION OF PLATINUM AND PALLADIUM PHOTOGRAPHS"
    http://cool.conservation-us.org/jaic...34-01-002.html

    Although it still lacks details as to the exact causes of the deterioration of the paper base as seen in some Pt/Pd prints, which seems mainly due to a lack of scientific or conservation research in this field, it definitely is worth a read for anyone doing or wanting to venture into Pt/Pd printing.

    Also see the remark in section 3.5 of this article:

    "Due to stability problems associated with the paper base, platinum printing has turned out to yield far less permanent photographs than was thought or hoped. The state of old platinum and palladium prints is now of great concern. Investigation into why and how platinum prints deteriorate has been based exclusively on the study of existing prints, most of them several decades old (Rempel 1987; Reilly 1986; Flieder 1985; Norris 1985). The tests described below offer additional insights into the impermanence of platinum and palladium prints."

    *** Edit ***: Now read it all. A bit disappointing is that the article mainly focusses on setting a kind of baseline for the possible composition of historic Pt/Pd prints, and how they were processed. The results don't give any further insight into the process of the degradation of the prints, nor the impermanence, despite the suggestion of that in the above cited text.

    And here is another article from the Alternative Photography Website showing some more real world examples and photo's of the effect of Platinum on paper and the "mirror-image" formation, and two theories (but no definite answer) as to their formation (1 - mechanical transfer of Platinum particles, 2 - catalytic discolouration of paper fibres caused by the contact with the Platinum)

    Article by Taylor Whitney:
    http://www.alternativephotography.co...int-discussion

    And a reference to conservational deacidification of Platinum prints (not a full article, can only be accessed directly online by participating institutions):
    http://www.jstor.org/pss/1506762

    Marco
    Last edited by Marco B; 06-06-2010 at 08:34 AM. Click to view previous post history.
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    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  7. #27
    Marco B's Avatar
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    And another source that discuss a possible residual iron problem in Pt/Pd. Actually, from what I read up to know, residual iron seems to be playing a role as well, don't know if it has a connection with the catalytic properties of Pt/Pd by as well, but it is know iron cations can cause troubles by themselves, see this other thread I recently started here on APUG:

    A Conservation Treatment to Remove Residual Iron from Platinum Prints

    This article also raises the question how much of the deterioration is attributable to the catalytic conversion of SO2 to SO3 by platinum, and how much due to residual iron. Of course, both deterioration processes could work in conjunction.

    It seems that "clearing" the print is of utmost importance, and was not always done correctly historically (and may of course not always be done correctly today...), as some historical prints with discoloration showed residual iron by XRF spectrum analysis.

    Interestingly, it seems there are highly sensitive test strips available (see this page) that can detect residual iron at levels as low as 1 ppm as well. Maybe they could be used as a test for proper clearing of Pt/Pd prints. In addition, the recommended calciumphytate or magnesiumphytate chelating agent baths used for removing excess iron in iron gall ink corroded documents, might be of use too?? Maybe as an extra bath after the now common EDTA clearing?

    Marco
    Last edited by Marco B; 06-06-2010 at 09:10 AM. Click to view previous post history.
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    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  8. #28
    Marco B's Avatar
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    Mike Ware's comments on the issue

    Hi all,

    Some good news. Mike Ware was kind enough to contact me after having seen my thread here on APUG, and give some more insights into the problem, as seen from his knowledge. He also gave permission to publish it here, so I have added his comments here in this post as he send them to me via e-mail.

    *** Mike Ware's comments on the topic: ***

    1) Empirical evidence: anyone who has handled a number of unmounted historic platinotypes (ca. 100 years old) knows that they *can* be very fragile (but are not always so). The phenomenon is history-dependent. I have examples of both in my possession. The issue of acidic embrittlement of the paper substrate of historic platinotypes is well-known to photograph conservators. It has been attributed to the catalytic effect of platinum 'black' promoting the oxidation of sulphur dioxide SO2 to sulphur trioxide SO3, which with water forms sulphuric acid H2SO4, which is non-volatile and concentrates in the cellulose fibres, splitting the chains and weakening the structure. All this you know already.

    2) Many years ago, I supervised a "quick and dirty" unpublished experiment to test the general idea:

    A piece of cellulose paper was half-coated with platinotype sensitizer, exposed, and fully processed to produce maximum density of black Pt.
    It was cut into four pieces, two white, two black.
    One white and one black piece were separately macerated in a liquidizer, and the pH of each measured instrumentally as a 'control'.
    The other white and black pieces were exposed to an atmosphere of sulphur dioxide gas (ca. 1 atmosphere) for 3 days in a closed vessel.
    These two were then 'pulped' and their pH's read.

    The pH results were:

    Controls: white paper 6.3 black Pt 6.1

    SO2 Gassed: white paper 4.5 black Pt 2.6

    These rough figures seem to provide evidence that 'platinum black' catalyses acid formation in the paper.

    If you assume a sort of concentration/time reciprocity law for the "gassing" (I have no evidence that this is valid!) it suggests that 1 atmosphere of SO2 for 3 days is about equivalent to a concentration of 100 ppm for 80 years.
    This is an unreasonably high 'gas exposure' for an historic platinotype: outside levels could be about 1 ppm. Indoors maybe more.
    Obviously this rough experiment needs to be better controlled and the variables explored. In particular the Relative Humidity of the atmosphere needs to be controlled, because I think the water content may prove to be a significant variable. It would also be interesting to see what happens with a pure palladium print.

    3) Figures for the SO2 content of the atmosphere at various times and places are available.
    For instance the "Great London Smog" of 1952:

    http://www.ace.mmu.ac.uk/Resources/T...uality/02.html

    saw a rise to a maximum value of SO2 level quoted as 1.34 ppm, compared with a previous mean of about 0.1- 0.2 ppm. Since the Clean Air Acts of the late 1960s, levels of SO2 in some places (e.g. Manchester) have dropped by a factor of 10, from about 0.5 ppm to 0.05 ppm.

    I would be interested to hear of any figures estimated for the typical domestic atmospheres of the late Victorian era, when many historic platinotypes were made, and gas, coal and coke were being burnt openly in confined environments, as well as in the industrial discharges.

    4) "Image offsetting" by platinotypes is a well-known and characteristic effect, as illustrated by Jim Reilly and Taylor Whitney. It could be due to two things: the catalytic acid production diffusing across and degrading the opposite contacting sheet, or even to a more direct surface catalysis of the oxidative degradation by air of the polyphenolic lignin macromolecules in some wood-based papers, giving rise to quinoid structures with typical yellow-brown chromophores (same thing that causes colour of oxidised hydroquinone developers, and yellowing of newsprint). There should have been some research on this by now, but I don't have the infra-red instrumentation needed.

    5) None of the above applies to palladium, as far as I know. I've not heard of embrittlement in historical palladiotypes (possibly because they are much rarer than platinotypes) and I haven't seen any instances of 'offsetting' with palladium - but this too may be a scarcity effect. Most so-called "platinum printers" today are actually making palladiotypes, substantially, if you examine their recipes, (and bear in mind that platinum is usually intrinsically 'slower' to deposit than palladium). Gottlieb's article that you cited, for instance, is actually confined to palladium in his experimental work despite his title: it does not cover the behaviour of platinum at all.

    6) Modern clearing of Pt/Pd using my recommended sequence: Na2EDTA - metabisulphite - Na4EDTA, (see my Website) leaves the paper at a favourable pH compared with the HCl baths of yesteryear. Iron(III) stains can, however, be removed retrospectively by treatment with dithionite/EDTA (Rees & Gent at the V&A - a piece of research that I part-supervised.)

    So, all in all, the "platinotypes" of today are much less at risk from acid degradation than those made a century ago, for a variety of reasons:

    most of them are not platinotypes anyway
    they are now better cleared of iron(III) in non-acid baths
    the atmosphere contains much less SO2 to form acid
    the papers used are generally of heavier weight

    So, in a sense, Loris is right: There's little to worry about for the present practitioners!

    **************************

    I intend to write my own "concluding remarks" based on all I read and Mike's additional comments. Will post them here soon.

    Marco
    My website

    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  9. #29

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    Thanks Marco & Mike Ware for the encouraging information. I prefer straight Palladium prints due to their tone, so very interesting if they're also less vulnerable to pollution.
    van Huyck Photo
    "Progress is only a direction, and it's often the wrong direction"

  10. #30
    Marco B's Avatar
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    A few more points:

    - Found some more interesting info. It seems the Getty Museum, and specifically the Getty Conservation Institute (GCI), is currently conducting a large study into the wide array of (historical) alternative processes.
    http://www.alternativephotography.co...t-at-the-getty

    Interestingly, they mention some of the historical Pt/Pd prints they encountered, had significant red staining due to insufficiently clearing of iron sensitizer, although, to be honest, if I read "dark red highlights", I am beginning to wonder if the photographer bothered with clearing his prints at all... :o

    "Analyzing a large number of both historical and modern iron-based alternative process photographs has allowed us to assess different types of developing and clearing procedures. We have experienced platinum prints with dark red highlights due to now fully oxidized residual iron from insufficiently cleared or washed platinum prints. Our analysis of modern iron process prints provides the artist with some insight into their working technique and helps to predict potential changes of print tonality due to aging. To date we haven’t found any iron-based prints that do not contain some residual iron even after very good processing, but our analysis of Steven’s prints showed that his prints will be very stable with minimum chance of tonality changes due to iron residue."

    - This clearing issues or removal of iron is definitely a big issue as well, as remaining iron is well known to cause paper degradation as well besides causing a visible coloured stain on the print.

    The process behind this is about the following (from this article):

    Fe2+ + O2 + H+ --> Fe3+ + HOO•
    Fe3+ + HOO• + H+ --> H2O2
    Fe2+ + H2O2 --> Fe3+ + OH- + OH•
    OH• + Cellulose --> depolymerisation

    Where OH• is a highly reactive Hydroxyl radical, as you can see created from the remaining iron in the print. Paper is mainly cellulose, and depolymerisation means the chains of cellulose are broken down in smaller pieces, causing embrittlement of the paper.

    - Despite both my and Mike's remark about SO2 levels having dropped significantly in the past two decades due to mitigation efforts at the sources, we are still not at the very low pre-industrialization levels. For those wishing to determine their own environment, I have now included "The Lichen Scale" as attachments. As I wrote before, lichens on trees are very susceptible to SO2, and give a good indication of SO2 in the local environment. Looking at the scale, and knowing our Dutch forests, I can tell I almost never see lichens of the group 7, and rarely 6, meaning levels are generally above 50 microgram / m3.

    Interestingly, if you look at historical 17th century pictures of the Netherlands, painters did depict lush lichen growth on trees, another indication air used to be much cleaner. And you can still see beautifully covered trees in for example parts of the UK, with its clean ocean air.

    By the way: for anyone working in education: this is a very nice experiment to make children aware of air pollution. Have them map out the lichens in and around your town. Scale is valid for moderate central or northern European climates, but I guess it will work in other wetter climates as well, although the lichen species may or will be different.

    Marco
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    Last edited by Marco B; 06-08-2010 at 08:39 AM. Click to view previous post history.
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    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

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