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  1. #11
    jd callow's Avatar
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    This is extremely impressive.

    *

  2. #12
    Photo Engineer's Avatar
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    I take back what I said about reversing the times of addition of the silver in the second and third additions. This is a single run emulsion, and therefore does not require an accelerated growth.

    Sorry for the confusion. I would go with the times given by Jim.

    PE

  3. #13

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    Quote Originally Posted by dyetransfer View Post
    Hi Ron - Could you describe what you have done with this emulsion formulation? I remember you talking about having made a taking film from this emulsion. Did you add any sensitizing dyes? Gold Sensitizing? What approx. speed did you acheive? Also, you did an analysis of the iodine deposition (interior -vs- exterior of the AgBr crystals), and perhaps have some suggestions for improving the efficiency?

    My grain size was optimized for its hardening effect on the gelatin (too small doesn't work), but I think that the grain size is appropriate for a taking film. I saw the cubic crystals under a microscope at FK, it was fun to actually see this - makes it seem more real than theoretical.

    Regards - Jim
    Jim,

    Would you please email me your phone number? I am a carbon printer and have been meaning to call you on behalf of Bud Wilson to talk about the coating machine and potential applications. Bud provided me with your number but I got tied up with travel and appear to have misplaced it.

    Sandy King

  4. #14

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    What is this "Melanex" that this emulsion was coated on? Is this different from the bases (Tri-acetate, Estar, Polyester) used for camera films?

  5. #15
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    It is 7 mil (0.007") Estar for all practical purposes.

    One side is subbed to accept aqueous coatings.

    PE

  6. #16

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    supplyers for this materal?

    Quote Originally Posted by Photo Engineer View Post
    It is 7 mil (0.007") Estar for all practical purposes.

    One side is subbed to accept aqueous coatings.

    PE
    pe-

    who supplys/vends this material ?- under what catagory is it listed? what is it's intended use? who uses it besides dt workers?

    cost??? can get small quanties? rigid or flexible?

    is this similar to what the art world calls "prepared" acetate?- which many times is not an acetate but a poly-estar

    thanx

    vaya con dios

  7. #17
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    Jim Browning has posted at his web site all of the sources for every product he uses in the formula posted above. Please read his article carefully and look at the pictures. Everything is there that you need.

    PE

  8. #18
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    substitution / addition of dyes?

    Quote Originally Posted by Photo Engineer View Post
    Hardening the coating and adjusting the coating levels of silver and gelatin will give a pretty respectable camera film.

    PE
    Hello PE,

    Thinking along the same lines, could erythrosine be added to or substituted for the tartrazine (yellow dye) in Jim's emulsion? And if so, would it be done at the same point as the tartrazine?

    Thanks,

    Bob M.

  9. #19
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    Erythrosine is a sensitizing dye, tartrazine is an acutance dye or absorber dye. They serve two different purposes. Both or either could be used to get different effects.

    Tartrazine will improve sharpness, and Erythrosine will add green (ortho) sensitivity. The amount of Erythrosine will have to be determined by trial and error, as will the optimum method of addition.

    PE

  10. #20

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    Quote Originally Posted by Photo Engineer View Post
    Jim Browning has posted at his web site all of the sources for every product he uses in the formula posted above. Please read his article carefully and look at the pictures. Everything is there that you need.

    PE
    I got this film (1 mile roll x 50") from ICI some years ago. Since then, the Melenex line was sold to Dupont. I think they have an 3 roll minimum, costing somewhere around $ 8,000. You would need to provide them your railroad siding number to receive the rolls (this is what ICI asked me, I'm not joking! they sent the roll via truck though). In addition, you have to have a very heavy dolly made with large pillow block bearings to hold the 1,000 lb roll.

    Regards - Jim Browning

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