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  1. #1
    Mustafa Umut Sarac's Avatar
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    1920s Kodak to Dichroic Filter Design

    I am interested in scientific especially laser optics , electronics , mechanism catalogs and I found that it is possible to order your special sensiometry filters from military , remote sensing filter makers.

    I watched a excellent movie someone posted from kodak , it was 1920s kodachrome movie film.

    It is said it was two color film and it makes two color special order dichroic filters.

    Can anyone post these each of sensiometric curves of this two color film ?

    I think this is the biggest step to get these excellent colors back to photography.

    Thank you ,

    Mustafa Umut Sarac

    Istanbul

  2. #2
    Mustafa Umut Sarac's Avatar
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    May be we can make a stereo MURA or pinhole camera - escaping from special color rendition of lens - and attach these two filters and take great colors with 3D.

    I dont know the chemistry but may be we can find the chemicals for these original colors , prepare gels and injection or spin mold and mass produce these colors as filters.

    May be filters might optimized for tri x film also but I think filter guys can do it. They landed to moon at 60s .

    Mustafa Umut Sarac

    Istanbul

  3. #3
    AgX
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    For two colour separation work the visible spectrum is not divided in three but two.

    Typically cyan and orange.

  4. #4
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    Two color processes were common in the early days of color photography. Many used prisms/beam-splitters to make two different-colored images on the same strip of film. The same prism was used upon projection. I don't think it would be too difficult to find this information and/or the filters themselves.

    What is stereo MURA? Could you please elaborate on your pinhole idea?

    That was a very cool film reel, I guess I didn't realize it was two-color!

    update: here are some starting points.... (some patent links, which might have spectral characteristics)
    http://en.wikipedia.org/wiki/RG_color_space
    http://en.wikipedia.org/wiki/Technicolor
    http://en.wikipedia.org/wiki/Kinemacolor
    http://en.wikipedia.org/wiki/Bi-pack_color
    http://en.wikipedia.org/wiki/Prizma
    http://vancouver.ca/ctyclerk/archive...ges/MI-058.htm
    Last edited by holmburgers; 06-30-2010 at 02:38 PM. Click to view previous post history.

  5. #5
    Mustafa Umut Sarac's Avatar
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    MURA is a technology which multiple pinholes placed in front of film in a fractal order. Result is not a picture but a blur. Computer decipher it. It is a basic lens but very much light gathering capacity.
    We have two filters and will have two lenses and stereo image. One is right , one is left.
    MURA or pinhole do not distort the color and this is essential for this purpose.
    I am not after finding 80 years old hardware but finding a simple technology for new hardwares.
    So the sensiometric information is a must.
    AgX , what is cyan , what is orange ? There are millions of possibilities. And I am after reinventing the original if it is possible.

  6. #6
    Mustafa Umut Sarac's Avatar
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    And some say red orange , green cyan. I think someone have information on finding the sensiometric information.

  7. #7
    holmburgers's Avatar
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    You could pick two spectra points and just experiment. Or, you could find the 80 year old hardware and study it. Either way, check the patents for the old processes.

    Do you have any MURA links? It sounds fascinating and I couldn't find any (yet).

    Update, found it.... http://www.paulcarlisle.net/old/codedaperture.html

  8. #8
    Mustafa Umut Sarac's Avatar
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    Thank you Holmburgers , I just started to dig the links. Thank you.

  9. #9
    Mustafa Umut Sarac's Avatar
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    I cant study old hardware , Its a huge difficult option. I will look to the patents. But if someone have detail in his her hand , please post .

  10. #10
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    IIRC, some of this early work was done by Sir Robert Hunt of Kodak Harrow. One of the first color enlargers made by EK was designed by Bob and was placed in the George Eastman House this year. I believe that it too used dichroic filters. The early Kodachrome predates his work by quite a few years though.

    PE

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