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  1. #41
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    Quote Originally Posted by Photo Engineer View Post
    Ray, I would say that the published to unpublished ratio of work at EK is on the order of 1:100. That means that a lot of work is never revealed.
    I think this is true of all major research-based corporations and many gov't funded projects. If you are working on something small, it gets published. If you are working on something big, it doesn't get published. At least not for many years.

    NDAs are the bane of my existence. Well, those and MTAs (materials transfer agreements) which can be even worse.
    "Only dead fish follow the stream"

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  2. #42
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    Thanks all for the clarifications.

    Given what Mitchell said, I believe it was due to the fact that he was not given a lot of information by EK researchers for one reason or another. I know that George Byrd was given all of the facts available though and I met with him several times with specific orders to disclose all! I'm not sure, but I believe that Byrd was with Princeton at the time.

    PE

  3. #43

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    Quote Originally Posted by Photo Engineer View Post
    Those were probably made with an Ammonia digest and would be considered rounded cubes or rounded octahedra.

    PE
    RE,
    Will the use of high levals of Br in relation to Ag also serve to round corners?I mean all of the Br in the batch prior to any Ag adition.
    Bill

  4. #44

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    Another question about rounded corners:
    Will speed and duration of mixing serve to round the corners? Reduce crystal size? Perhaps the relatively low shear of a magnetic stirring bar would do niether?
    Bill

  5. #45
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    Bill;

    High bromide will not help form cubes to allow rounding of corners, but if you add a lot of bromide after the cubes are made, then you have created the conditions that there may be some rounding due to solvency effects during digestion.

    Speed and duration of mixing may or may not influence this effect. Generally, IMHO, it does not. Neither does addition rate. Addition rate affects size and grain size distribution. Of course, slow mixing will tend to create a greater mix of crystal types or even an unusable emulsion. I have done that with some makes with poor mixing at small volumes of starting materials.

    PE

  6. #46
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    Quote Originally Posted by Photo Engineer View Post
    Given what Mitchell said, I believe it was due to the fact that he was not given a lot of information by EK researchers for one reason or another.
    That could be it. My understanding was that Jack had some results for new ways to sensitize that EK didn't want to invest, and ther was a particular person at EK with whom he had a falling-out over this. So Jack went to Fuji. Of course, higherups at EK and Fuji must have known already that the heydays for research on silver halide sensitivity were over. As you have noted elsewhere, there is a *lot* of fantastic research on the shelves that may never go to market.

    Anyway, like I said, I know nothing of emulsion science. I would just guess that a crystal with well defined electron and hole migration paths would be advantageous. The surface mobilities of the electrons and holes on the crystal must be very important. If the particle is faceted then I guess there will be sensitization hotspots, and I imagine the sensitizers adsorbing preferentially in a number of clusters related to the number of facets (or perhaps facet boundaries).
    Last edited by keithwms; 12-23-2009 at 06:02 PM. Click to view previous post history.
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  7. #47
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    You left out "twinning".

    We have investigated just about everything you can imagine. Think about this... Maybe we had already done what Mitchell was proposing and either found it a dead end or were using it as a trade secret. In either case, we would not divulge anything about it. In fact, his going to Fuji in either case would have been an advantage to EK and we would probably have let him, if he ever threatened anyone that he would do it.

    PE

  8. #48

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    Quote Originally Posted by Photo Engineer View Post
    You left out "twinning".

    His going to Fuji... would have been an advantage to EK....

    PE
    That was an erie smile... (PE) and a critical omission (Keith),
    since that is exactly where this research was put to use!

    How did Kodak benefit by Mitchell's ideas being used by a competitor? !!
    Last edited by Ray Rogers; 12-23-2009 at 08:07 PM. Click to view previous post history.

  9. #49
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    Ray;

    I think you will find that Kodak used twinning as well. In any case, thin t-grains were a Kodak invention and a Fuji invention at the same time, then Fuji, IIRC, moved towards thicker t-grains. IDK the exact sequence, but this was a fast moving field. And, Anabelle was working on 2 electron sensitization while Paul was working on dye layering.

    These latter two allowed Kodak to surpass anything anyone else was doing. It gave them at least 1 - 2 stops in speed with the same size grain (each method) and when combined it gave 2 - 3 stops. This has given them a commanding lead in Motion Picture films, just when no one needs it. And, you see, we are back to the original question - ie. what might we have seen in the absence of digital?

    PE

  10. #50

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    Quote Originally Posted by Photo Engineer View Post
    Ray;

    I think you will find that Kodak used twinning as well. In any case, thin t-grains were a Kodak invention and a Fuji invention at the same time, then Fuji, IIRC, moved towards thicker t-grains. IDK the exact sequence, but this was a fast moving field. And, Anabelle was working on 2 electron sensitization while Paul was working on dye layering.

    These latter two allowed Kodak to surpass anything anyone else was doing. It gave them at least 1 - 2 stops in speed with the same size grain (each method) and when combined it gave 2 - 3 stops. This has given them a commanding lead in Motion Picture films, just when no one needs it. And, you see, we are back to the original question - ie. what might we have seen in the absence of digital,

    PE
    Yes, quite right. The nursing and pampering of tabular grains was a Kodak moment even though technically, the tabular grains themselves were not really invented, but had been formed inadvertenly many years earlier. (I would say that it was actually the emulsions that used tabular grains that was invented but anyway, getting back to the thread...)

    I think the issue here was latent image dispersion and how to concentrate the electrons in, to use Keith's words, an optimum "hot spot".

    I have not really looked at the work directly, so I am only guessing but if Anabelle and team was looking at Mitchell's work at the same time as they were working on 2 electron sensitzation, well, likely they would have been less impressed, but I think you are correct and we do come back to where we would be today (and tomorrow!), in the absence of digital.

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