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  1. #11

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    "Fictional situation: in 2030, there are less and less films to choose from, and people are uncertain how long they will be available.... "

    2030 ?! I never thought of you as a "diehard optimist".
    More like 2010 !!!
    I know that I have never said this to you befor,PE, but Thank You! for the effort you are going through for everyone's sake. Reading this thread for the first time today, I am actualy getting a little "choked up". O r maybe its just the concentrar
    ted ammonia fumes.
    Bill

  2. #12
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    Quote Originally Posted by Anon Ymous View Post
    Hello PE...

    Do you really need to have multiple layers in order to make a VC paper? IIRC, there are available ready made VC emulsions that can be hand coated. Or is it needed only for the full range of contrast grades?
    Ok, single layer VC emulsions....

    These are specially engineered to prevent "crosstalk" between the emulsions if coated as one layer. This is presently beyond my capabilities. In fact, when I suggested a VC Azo type paper, it was roundly rejected here on APUG and so due to the difficulties, I went ahead with a graded Azo type paper.

    It is possible, but very difficult! I'll let you do it.

    PE

  3. #13
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    Bill;

    I am happy to do this. It is a fun effort and keeps me out of trouble.

    PE

  4. #14

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    Quote Originally Posted by Photo Engineer View Post
    ...It is possible, but very difficult! I'll let you do it.

    PE
    Oh, got it...

  5. #15
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    BTW, single layer color materials are possible as well. They are called "mixed packet materials". They are also very difficult to do. I'll leave them and most all color to you.



    PE

  6. #16

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    Quote Originally Posted by Photo Engineer View Post
    BTW, single layer color materials are possible as well...
    :o Really? So, tell me if I got it right..

    Since you don't have filters between the layers to block specific wavelengths, you need to make a mixture of emulsions, each of which is sensitive to specific bands. And the spectral sensitivity chart of each of these emulsions wouldn't be "bell-like", as it is with today's color films, but rather steep and flat. Did I get it right?

    TIA

  7. #17
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    No, the spectral sensitivites of a negative-positive color paper would be exactly the same as they are today. Endura's sensitivity curves can be seen on the Kodak web site. The speed ratios would also be the same with a fast blue, medium green and slow red. (about ISO 100, 50 and 25 respectively)

    PE

  8. #18
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    I'm still believing in 35mm!

    After all, we have been able to make currently still just one quite decent picture on an own emulsion (this one: http://www.students.tut.fi/~alhonena/OMAFILMI.jpg ) and it happens to be a 35mm frame - or at least was before processing ! But it wasn't ISO400 but rather ISO5 to ISO10 so there's still a long way......... Of course, dust and coating defects are a bigger problem in 35mm, but on the other hand, at least I believe, the chances that the whole frame has more uniform coating goes up, especially if you do small coatings... But I will keep my belief and try my best after learning more -- be it LF, MF, 35mm or even 16mm MP film.!


    And Bill, many people predict every year that film dies or almost dies "in few years". Nothing like that has happened so far, and new products like the new TMAX films are released even in 2008. I think it's just realism to believe that nothing will change much in 2010, or 2011, or 2012, or...... That's why I picked a date so far in the future, that no-one of us can see what it will be like --- there might be a real renaissance for film photography, or it may die almost completely! But one thing is sure; I'm going to do what I want to do, even if it was to reinvent the wheel .

    Best luck to everyone! Keep your inner emulsions boiling!

  9. #19
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    Boiled emulsions, wow, that is an old method abandoned just about 100 years ago.

    Actually, 35 mm is possible, but slitting, chopping and perfing will be complex operations as will the prevention of dust during the coating, drying and finishing process. Equipment will have to be made to help with the finishing. And, it probably will need some sort of machine to coat the lengths needed for 35mm. The thinner support is also a problem. You see, getting good subbed estar or acetate is rather difficult but glass is with us forever (or at least a long time).

    MF film is made difficult by the need for thin support as well. The paper backing will be difficult to devise and this is why I have a 120 coater. I am also saving my 120 paper backing. I have a drawer full of them.

    PE

  10. #20
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    My last post seems to be a bit foggy, I had too high temperature due to swine flu . You were right that it's quite unpredictable with these pig-related things instead of cows.... But now I'm eating these to get proper Dmax: http://www.vitabalans.fi/en2.php?k=4165

    I believe that PET will be with us for a long time now on as a rollware for many, many purposes... I've two rolls of thin 40x30 cm sheets. I'll try the corona discharge subbing as soon as possible and will report the results.

    And, 135 films with 12 or even 16 exposures could be hand-coated. They are still quite practical...

    And I have been thinking..... There's cotton and acetic acid available in grocery stores.... Hmmmmm!

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