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  1. #11
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    Quote Originally Posted by Ed_Nyari View Post
    Personally I have no problem with that, but those are not curves from the product sheet that Kodak usually publishes for free, but are actual results from the study (experiment). The study was originally published in a magazine, and is now being soled.
    So basically it would be piracy. I don't know what is the policy of this forum about that. I don't want to offend anyone around here.
    Ed;

    A lot of that data on interimage has been published in several textbooks. If you could give the authors names, I could probably find some complimentary data in the texts that I have here.

    There is a chapter on this in Mees and James, and also the complete textbooks "An introduction to Color" by Ralph Evans and "Principles of Color Photography" by Evans, Hanson and Brewer. Some of this includes the matrix math for the dyes and there are characteristic curves shown.

    The exposures referred to are called "undercut" and "double undercut" exposures. They show how one color can 'undercut' another or how two colors can 'double undercut' another.

    Much work on Ektachrome was done by Neuberger and Murray. Work on negatives was done by Bello and Kofron and Zwick.

    PE

  2. #12

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    Ron

    The authors are Hanson jr. and Horton


    Helen.
    I like the look of those slides you posted. Do you perhaps have some gallery set up somewhere where I could see more of them?
    If not, could I get a larger sized version of the second one? I'd like to take a closer look at it.

  3. #13
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    Ed;

    Then with W. T. Hanson as author, you get the author of 2 of the primary textbooks on the subject. The texts will probably go into more detail. Work by the others will be more up to date.

    PE

  4. #14

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    Can these books be purchased in the same way (as E-books)?

    By the way, I actually bought this because it speaks in the context
    of early color photography, which is what I'm really interested in: early color films

    I'll probably look for more of such texts

  5. #15
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    Ed;

    I really have no idea. I bought these in the 50s as first edition hard cover books. Sorry I can't help there. They are part of a library and I have never given it much thought.

    PE

  6. #16

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    Can you tell me, which of these two books speaks more about concrete and less about color theory in general. Because I'm really not that interested in general color theory as much as getting to know more about actual characteristics of materials of that time, both negative and reversal.

    Do any of these books speak of concrete problems found in materials of that age, and show their sensitometric and colorimetric data?

  7. #17
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    Neither book has much concrete data of that sort. It is a lot of theory and math with dye curves and matrix algebra.

    Most of what you describe was done, but not published. I'll see what I can find.

    PE

  8. #18
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    Example of color undercut exposure

    I have had an envelope of these in my darkroom since the 80s. This is an 80s Ektachrome 64 printed onto either Ektaflex R or Radiance paper. I cannot tell which.

    The exposure is a series showing the color gamut from red to cyan. To do justice to this, the entire series consisted of neutrals, magenta to green, yellow to blue and etc, and was usually both examined spectrophotographically and densitometrically.

    The exposure was made on the film using WR 98,99 and 70 filters with a crossed step chart, and the prints onto the paper were made with corrected white light.

    It was also done on negative film. I'll try to post more later. I have one other set.

    PE
    Attached Thumbnails Attached Thumbnails undercut1.jpg  

  9. #19
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    After reading this over, I think it needs clarification. The experiment consists of 3 parts.

    1. Expose film to WR 98, 99 and 70 filters to make the original grid. This shows what the film can do all on its own.

    2. Expose the paper to the same grid with the same filters to show what the paper does on its own.

    3. Expose the film results from #1 onto the paper with white light to show what the SYSTEM is capable of.

    Optional extras include real photos shot alongside and printed alongside these with a reference color checker in the scene, and also with resolution charts.

    This is part of the design stage of Ektachrome Film and Ektachrome Paper.

    PE

  10. #20

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    Seems like some serious red blocking up.

    Thanks, this is really interesting. How precise is the scan?

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