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  1. #31
    Petzi's Avatar
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    Buy it!

  2. #32
    Petzi's Avatar
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    Quote Originally Posted by Gerald Koch
    This is where you are wrong. Each of the three emulsions layers must be developed separately and must be exposed to light from a specific side. I believe the center layer is the last to be developed and may use a fogging developer.
    I wonder how to control that the light reaches only the specified side of the film? There has got to be some light scattering in the machine? How do you do it in manual processing?

  3. #33
    htmlguru4242's Avatar
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    To Petzi, I'd imagine that you'd put the side to be exposed down, and shine that color light up, and it would be very low intensity. I wouldn't think that a little scatter would matter, as the light would be of a certain color that the other layers are not compeltely sensitive to.

    Maybe PE would be able to answer this specifically ...

  4. #34
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    Quote Originally Posted by Petzi
    I wonder how to control that the light reaches only the specified side of the film? There has got to be some light scattering in the machine? How do you do it in manual processing?
    You can expose both sides if you like, the important one is to expose is the emulsion side.

    By the way, I assume you guys have no idea of what difficulties and expense it would be to process Kodachrome at home properly, otherwise I doubt if you would waste your time even thinking about it.
    Don Bryant

  5. #35
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    It is essential to expose the back, and only the back of the film to red light and the front and only the front (emulsion) side to blue light. It is also essential that only one of these be done at a time and that only the corresponding color developer be used afterwards to finish development in that layer.

    The exposure is done using a small lamp with the film clamped in a holder. We had 35mm holders or 4x5 holders that kept the film rigid and then placed them in front of the appropriate lamps for exposure. I believe a WR29 or a WR70 was used for the red exposure. The other side of the film was protected from light exposure.

    Red was done first.

    Yes, we could get Kodachrome in 4x5 sheets, even up to the end of the project, and no, no one wanted them so it was a very rare thing.

    PE

  6. #36

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    Quote Originally Posted by Craig
    After looking at the patent, its nice to know exactly what is in the kodachrome chemistry, but tough for anyone but an industrial chemist to obtain the chemicals and mix the solutions.

    Interestingly it specifies a processing temperature of 27C, I thought that it was 38C?
    Couldn't one get the needed chemistry from say oganica.de ? All I can tell is they make chemistry for colour couplers and masks, the names and cross checking of them is unfortunately beyond me Someday (somemonth anyways) soon I promise will read up on organic chemistry, esp colours.

  7. #37
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    The names of the couplers and developers are in the patent. You can just look them up, copied as-is from that information. I cannot get to the URL you refer to, so I cannot help.

    PE

  8. #38
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    The correct URL is http://www.organica.de

  9. #39

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    Quote Originally Posted by sanderx1
    Couldn't one get the needed chemistry from say oganica.de ? All I can tell is they make chemistry for colour couplers and masks, the names and cross checking of them is unfortunately beyond me Someday (somemonth anyways) soon I promise will read up on organic chemistry, esp colours.
    I'm not sure why I got involved in this thread at all, I don't shoot kodachrome (among other things due to non-availablity) anyways... organica.de doesn't have all or even close to all of those. www.chemos-group.com seemed to have anything listed that I bothered to pasdte into their search but again, I won't be using the stuff so I'm not going to ask them for a quote. www.chemexper.com appears to be a portal for finding suppliers and for most thinsg apparently somebody will be willing to sell in small quanities.

    I'll take more care in the future as to what threads I go anywhere near, never mind posting in.

  10. #40
    Ed Sukach's Avatar
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    Some time ago I promised to upload the Kodachrome Process (K14) as published in an issue of Camera and Darkroom (Magazine sadly missed - a great deal). Without trying to retype and re-format, here is a .jpg scan (there was a great deal of struggling as it was). I hope it is readable.

    K14 Processing:
    Last edited by Ed Sukach; 07-27-2007 at 08:32 AM. Click to view previous post history.
    Carpe erratum!!

    Ed Sukach, FFP.

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