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  1. #21
    jovo's Avatar
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    Alistair Inglis finally got a website. I looked into the feasability of using his unsharp mask products. HOLY SPIT!!! That stuff is EXPENSIVE!!!
    And probably unnecessary too...if digital unsharp mask is any indication, it's way too easy to over sharpen, although some is necessary for the miserably low resolution of web presentation. I've never felt sharpness was an issue in any of the work I've ever done except when I've clearly made errors in depth of field or plane of focus settings, and nothing will make those mistakes go away. So I'll save the bucks that might have gone into USM and direct them to another lens for my 4x5, which I can't get enough of it seems.

    In any case, thank you all for your input on this. It's very reassuring to hear the drawbacks of pyro put in perspective. I agree with those who've declared his column irresponsible and needlessly alarmist after offering a larger, rational view of the subject. I'll get some gloves and use a dustmask when mixing the stuff.
    John Voss

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  2. #22
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    Quote Originally Posted by Jorge
    IOW, you can feed an animal 250 mg/kg of pyro for 1 month and kill it, or you can feed it 5 mg/kg for one year and kill it. You need to pick the appropriate dose for the appropriate length of time exposed.
    Weston put his ungloved hands into both pyro and amidol working solutions on a daily basis for decades. Since none of it has ever touched my skin, I'm hardly worried.

    On the other hand, I am personally acquainted with one photographer whose lungs are quite damaged from having breathed pyrogallol powder. Good respirators are the better part of valor. We should be very careful when mixing stock solutions.

    Another great photographer who died with Parkinson's disease was Margaret Bourke-White. I do not know what her level of exposure was to any photographic reducing agents.

  3. #23

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    Bond's articl;e was stupid and irresponsible. No magazne should ever have pulished it. As stated abve he used T-Max whih is the worst choice for any pyro develper. he cited innuendo and rumor in his claims about Weston, and he was pitching his unsharp maskng and promising to reveal the secrets ofhis msking techniques in a future article and possibly if you take a workshop. Of course he would not fid a developr he has refused to try for 20+ years any good as he would be afraid it might sully his previous print sales.

    Whenyou read anysuch article by a name photographer one should as the follwing questions

    have they been given free equipment that they are now promotng?
    have they been given free supplies or been put on a retainer by any companies currently or in the past and are they promoting those products?
    Do they have any axes to grind,?
    Is there any self promotion going on for future articles, workshops, etc.

    Unfortunately this type of artcle just creates unneccessary scare and does nothing to promote photography.

    steve simmons

  4. #24

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    Steve,

    Hydroquinone is a member of the "Pyro Family" of the hydroxybenzene ring reducing agents. It is one of the reducing agents in D-76 (Howard Bond's comparison developer). When used in low sulfite or sulfite free developer recipes, hydroquinone produces a proportionally stained and tanned image, very similar to those produced by pyrogallol and pyrocatechol.

    Hydroquinone (p-Dihydroxybenzene) has the same molecular formula and molecular weight as Pyrocatechol (o-Dihydroxybenzene). Pyrogallol is 1,2,3 Trihydroxybenzene.

    All three of these hydroxybenzene reducing agents (hydroquinone, pyrocatechol and pyrogallol) are capable of producing excellent results with both TMX and TMY. This is from my direct personal experience, which includes controlled comparative testing.
    Tom Hoskinson
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  5. #25
    L Gebhardt's Avatar
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    For the users of Pyrocat and PMK what is a good film to test with, if one wants to redo Bond's test? I will be testing Pyrocat with TriX, HP5+, and FP4+. Do these stain well and show the benefits of pyro? Once I determine my development times I plan on shooting the same images and using different developers in my Jobo then printing them each on the same paper as my test.

  6. #26

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    Quote Originally Posted by L Gebhardt
    For the users of Pyrocat and PMK what is a good film to test with, if one wants to redo Bond's test? I will be testing Pyrocat with TriX, HP5+, and FP4+. Do these stain well and show the benefits of pyro? Once I determine my development times I plan on shooting the same images and using different developers in my Jobo then printing them each on the same paper as my test.
    All 3 films you mention will do very well with stainning developers. I use the photowarehouse film (which some say is relabeled FP4) and I get ecxellent results with pyrocat HD. OTOH if you plan to do the testing for enlargement, I would recommend Tri X as the best film for PMK.

  7. #27
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    My Grandfather died of Parkinson's disease and he never developed a piece of film in his life!

  8. #28
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    Did my first roll of Bergger 200 (35mm) stained in PMK tonight. It seemed to have a higher B+F level than usual- wet from the can (visually that is).
    Am I seeing a combo of stain+silver or something wrong? Will drying change things? Anyone else trying this combination?
    "Just because nobody complains doesn't mean all parachutes are perfect."

  9. #29

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    Quote Originally Posted by garryl
    Did my first roll of Bergger 200 (35mm) stained in PMK tonight. It seemed to have a higher B+F level than usual- wet from the can (visually that is).
    Am I seeing a combo of stain+silver or something wrong? Will drying change things? Anyone else trying this combination?
    Could be that pesky dihydrogen monoxide, I tell you the stuff is a danger to anything and everything.....

    Seriously now, give us more details. Did you do a prebath, an after bath, any chance of using hard water?
    All these are factors that cause greater b+f. Some films are unsuited for the after bath, since all it does is increase overall stain.

  10. #30
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    I agree that the article, esp the anecdotal item on Weston, sounds like crummy journalism?

    However, FWIW, just curious, what about the author's assertion that a more dramatic acutence gain can be achieved through unsharp masks rather than choice of (staining) developer. Anyone who has done/seen both have an opinion on this?

    As far as pyro is concerned, i have been cooking it down and freebasing it for months now, and i feel just fine.

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