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  1. #11
    Vaughn's Avatar
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    "Silver salts are sensitive to thought." from Ted Orland's Photographic Truths.

    Other than that I am not too worried about it. If a company makes a product for general consumption and the general public can't use it, then the company will have to withdraw it from the market. Specialized products still have to be able to be used by specialists without too many complications.

    Canon came out with cameras that use an infra-red sensor to advance the film...thus losing the users of infra-red sensitive film. Fortunately for Canon that user group was not too big.

    Vaughn

  2. #12
    AgX
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    Monophoto,

    Yes, your post is off topic because it is related to radiation; but I can tell you I've got a German scientific publication out of this period in my library discussing the effects of radionuclide fallout on the photographic industry.

  3. #13
    AgX
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    Vaughn,

    This seems to be an issue to all high-end materials on the market. And most probably all new material to come in future will be high-end. High-end in the meaning that the processes of image capture and image intensification/gain are much more susceptible to influences beyond radiation, influences coming from within the imaging chain.

    And to my understanding (maybe I misinterpreted what has been published) there are already problems within the industry.

  4. #14
    rmolson's Avatar
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    How sensitive

    Fallout fogging paper
    I can tell you from experience that radioactive fallout does affect film and paper. In the mid 60’s I was working in a photofinishing plant in Canton Ohio. Our Christmas rush was at it’s peak when suddenly our color paper went bad. No matter how we tried to compensate with our printers the colors were off and out of balance. As we used Kodak paper as everybody did, the Kodak tech rep was practically living in our lab. But no one could fix it. In desperation we sent all of our work to another lab, our competitor. They were not having the problem. Finally we dumped our entire stock of paper in storage and Kodak send a truck load of new paper. By then the season was passed. Years later a story turns up that the government quietly settled with Kodak for the lost of their production run when the fallout from the above ground tests drifted over Rochester.. I can not verify the settlement but I can verify that our paper went bad for no reason at all. Including our paper in a refrigerated storage unit.. We bought our paper by the truck load and that paper was the batch than had been contaminated.. .

  5. #15
    Photo Engineer's Avatar
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    Film is sensitive to radioactive fallout. After the first atom bomb tests and use, Kodak was forced to install some expensive equipment which included foot baths for shoes when entering and leaving sensitive areas. I remember walking through these running water baths all the time.

    As for general sensitivity, film is very sensitive to mercury vapor and formaldehyde fumes to name two. Mercury is strictly controlled in all areas of Kodak park. Employees were not allowed to use merthiolate (the mercury salt of erythrosine).

    Oddly enough, both formalin and mercury salts can do good things if added properly before coating, but will harm film after manufacture.

    Iron salts in film or in developer will harm film. Iron salts falling onto unprocessed film or paper will cause problems, so I use a filter to remove any rust from my lines.

    However, the bottom line is that heat is the enemy of all film. Film suffers heat death from any source including your car's glove compartment on a hot summer day. In fact, that is probably the primary limiting factor in making fast films. If they were fast enough, they would not survive long enough on store shelves to be usable.

    PE

  6. #16

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    Better speed and a better quality in AgHal is only possible when mostly all not well known mistakes of the past are solved. Then better times for AgHal can begin. But this means work for the details, of course a lot of little things never mentioned in scientific publications. This forum is the only, where you can find and inform some of the experts, who could have heard about disturbing factors from a real AgHal-production.

    Vaughn is right, if a product can only used from a specialist, it is not for common. But when the reason is found, why this product has to be a special product only for specialist, than it is your duty as a scientist to CANCEL THE REASON, and to realize a common product for common market. AgHal cannot wait or digital will take all markets from us.

    My research goal since 1992 was to detect all possible mistakes for highspeed halftone in monodisperse emulsions, now the last puzzlepiece is found. In a velvet for a cartridge (when details wanted, see my german aphog.de forum text) can exist anti-electrostatic agents, water repellents, anti-felting agents, softening agents, catalysts for non-creasing and non-shrinking finishes, and so on ... you can read on the other page here in apug.

    This finding happens to me last week, and I am happy about it, happy for a more stable future for analog.

    To this forum – why not starting with a list of all possible influence?

    Starting points:
    1.cameras – auxiliaries from other films, sweat from hands,
    2.cartridges – velvet auxiliaries, auxiliaries from other films in production of cartridge, storage conditions (X-ray, radon), plastic smell of plastic tube, sweat from hands,
    2a. rollfilm – backpaper,
    3.developing tools – silverscum, plastic softener and heat, once used with pyrogallol like PMK, cleaning and wetting agents, sweat from hands,
    4.developers – producing Mackie-Lines in large dense areas, water,
    5.fixers – producing Mackie-Lines in large thin areas,
    6.drying

  7. #17
    Photo Engineer's Avatar
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    Quote Originally Posted by Gigabitfilm View Post

    My research goal since 1992 was to detect all possible mistakes for highspeed halftone in monodisperse emulsions, now the last puzzlepiece is found. In a velvet for a cartridge can exist anti-electrostatic agents, water repellents, anti-felting agents, softening agents, catalysts for non-creasing and non-shrinking finishes, and so on ... you can read on the other page here in apug.

    producing Mackie-Lines in large dense areas,
    producing Mackie-Lines in large thin areas,
    All of the areas you list were subject to intense research at Eastman Kodak for years. There are more items that can be added to this list, for example how to increase micro contrast over macro contrast for improved edge effects, humectants to prevent creasing and shrinking, development accelerating agents, matting agents, antistatic agents and 2 electron sensitization using osmate salts.

    There are reduction sensitizers, and direct reversal agents similar to the direct reversal you have described here. Kodak has 20 years worth of research on the shelves at this time which has not been realized and this includes the new 25,000 ISO film mentioned elsewhere.

    This high speed film has the grain and sharpness of a conventional 400 speed film from what I saw of the samples. However, its shelf life is unknown as I noted earlier.

    PE

  8. #18
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    Ron, I'm not familiar at all with the chemical side of the sensitization process, so I'll ask a dumb question. Give the short shelf life of high speed films, might it be possible to complete the sensitization process right before capture? I mean, you'd get the emulsion and a sensitization kit, kind of like the daguerreotype kits that people went mad over. You'd go in the darkroom and swab on some nasty bromide concoction or whatever, and then you'd go shoot... and develop quickly.

    Or maybe there could be something like a reverse-order polaroid contraption, you'd feed the film into a chamber through rollers that would squish a packet of sensitizing goop over the emulsion layer. Then you'd shoot. And develop quickly.

    Or you could simply send us the film packed in dry ice

    Anyway, a colleague of mine, Jack Mitchell, apparently had a bit of a longstanding academic issue with some folks at Kodak regarding hole sensitization (as I recall); he lamented the amount of unused research at Kodak before he passed away a few months ago.
    "Only dead fish follow the stream"

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  9. #19
    Photo Engineer's Avatar
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    Keith;

    This procedure you describe is "hypersensitization" and is used by astronomers. They treat the film to hypersensitize it and then use it as the effect fades away over several hours.

    It uses Hydrogen gas.

    You are welcome to try it. Make sure your insurance is up to day and add me as a beneficiary.



    PE

  10. #20
    keithwms's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Keith;

    This procedure you describe is "hypersensitization" and is used by astronomers. They treat the film to hypersensitize it and then use it as the effect fades away over several hours.

    It uses Hydrogen gas.

    You are welcome to try it. Make sure your insurance is up to day and add me as a beneficiary.



    PE
    Ah H2 gas is no problem, I use it at 1000C all the time. A grad student came to my office and said, calmly, there are flames coming out of the furnace; is that normal? I didn't know whether to run up to the lab or run out of the building.

    Now H2 dosing in the field might be a bit of a problem.
    "Only dead fish follow the stream"

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