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  1. #11

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    Drew, I have no idea so far what kind of curves one might expect from this, but I believe one can tune the whole system for his/her needs (BW developer, % of dichromate etc)
    maybe tedious (painful), but doable

  2. #12
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    Ok, we were reminded above that there is a transparent version of Endura so that is not a problem.

    As for using film, yes it is more expensive. But, I think that the curve shape difference is what you may want to consider. Films have a contrast of about 0.6 while viewable transparency film have contrasts of about 2.5, or a viewable contrast of about 1.7. That may enter into your consideration of what to use.

    PE

  3. #13
    CMB
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    Take a look at Webb's 1940 Patent#2196133 :

    "This invention relates to improvements in photography, particularly color photography, and has for its principal object to provide a relatively simple process whereby superimposed silver images in multi-layer photographic material (film or plate) may be isolated in such a form that they can be employed as separation negatives. "

  4. #14

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    IDK about December 2011. But Duraclear used to be MUCH cheaper than Color Negative 8x10. I

  5. #15
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    I considered RA4 clear film for negatives on my Lambda, I decided to try Rollie Ortho 25 and now may move to Ilford Ortho 25.
    I believe this product would work very well, I have used it for over thirty years in a commercial setting for backlight display work.
    Someone here or on DPUG has tried it and said it was not sharp enough... Since the roll from Fuji(fujiclear) would cost over $2000
    I was hesitant to try this route, but if there are workers here that think it is a good avenue I would be open to a group purchase and running some film for interested parties.
    My platform is 30 inch roll and can give specs for each worker to try, length of roll is 164 ft, I also could get a smaller roll 20inch x 164 ft.


    Quote Originally Posted by wildbillbugman View Post
    IDK about December 2011. But Duraclear used to be MUCH cheaper than Color Negative 8x10. I

  6. #16

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    Are Endura and Duraclear/ Duratrans the same thing ? It has been years since I worked with the later. A yahoo search turned up both. Whats the difference, if any?
    I an realy interested in this project, although I cannot conceivably take on another project myself. What realy interests me is the possibility of making modern "digital" negatives without the "digital". These negatives use color to optimize UV blocking for processees like Carbon Transfer .
    Bill

  7. #17
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    Bill;

    The two are just roughly similar. The Kodak info sheet should show that the Duratrans or Duraclear have higher Dmax to fit the needs of the transparency market. Paper is made with lower Dmax. There is probably a contrast difference as well.

    PE

  8. #18

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    Ron, I checked the datasheets of both and, yes, there is some contrast difference.
    Bill, my basic idea was actually to NOT run the paper/transparency through RA4 chemistry, but to develop only the silver image (of a single color layer) and to keep it instead-with and ordinary (low contrast) developer and ordinary fixer
    I have an old box of RA4 paper somewhere-I might give it a try some of these days
    regards

  9. #19
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    IIRC, the silver image of the RA4 products is very weak. You may be disappointed in that. The materials are designed to give high dye density with minimum silver.

    PE

  10. #20

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    T-grain, Yes I understand what you want to try. My brain started wandering and I thought that, maybe Duraclear could be used to make the negatives similar to the principles used by people who make digital negatives. Here, the inks used in printers contain no silver and are low in D-max. Even the small minority of systens that use pigments instead of dyes (Epson K series and small brand copycats) are low in density.
    Varrious colors are used to block the UV crititical to exiting,usualy dichromate. My interest is 3 color Carbon.
    P.E., Inkjet negs contain Zero Ag.
    Bill

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