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  1. #361
    Photo Engineer's Avatar
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    The coupler names are in the patent for all to see. The only reason I would do anything is to show the actual structure, or one close to it. But then, if you search the name for the patent, or the Napthol I gave above, the structure is shown.

    Such as here: http://www.sigmaaldrich.com/catalog/...g=en&region=US

    PE

  2. #362
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    Future Kodachrome Colour Developing

    Has Stephen's exact process been documented here in this thread?
    Stop worrying about grain, resolution, sharpness, and everything else that doesn't have a damn thing to do with substance.

    http://www.flickr.com/kediwah

  3. #363

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    Quote Originally Posted by clayne View Post
    Has Stephen's exact process been documented here in this thread?
    No i dont think it has yet.

    Ive created this page for the Cyan Coupler on the Kodachrome wiki.
    Feel free to make any changes you feel are needed PE.
    http://kodachromia.wikia.com/wiki/4-Chloro-1-naphthol
    Last edited by Nzoomed; 08-26-2013 at 07:03 PM. Click to view previous post history.

  4. #364
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    Great, but that isn't a K-14 coupler. It's just a simple cyan producing coupler. And, by the way, you see the price of that stuff, yes? Now, go get a price on the real thing!

    On the other hand, for small quantities (say 100 rolls worth) you'd probably have to try to DIY it. So, just how DO you make 4-chloro-1-naphthol in your basement? Can it be done? Sure! But HOW is the (rhetorical) question!
    Last edited by kb3lms; 08-26-2013 at 08:09 PM. Click to view previous post history. Reason: Made it say what I wanted it to say.
    All this has happened before, and all this will happen again.

  5. #365

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    It is encouraging to see all the interest in developing Kodachrome film. Of course this is a classic case of reinventing the wheel. People interested in the process should look at J.S. Friedman's "History of Color Photography" chapters 10 and 23. The book is available online for free at:

    http://archive.org/stream/ost-art-hi...ge/n9/mode/2up


    Friedman outlines the process and names a variety of color couplers which may be used for the complementary colors, cyan, magenta and yellow.


    I think APUG should encourage someone with industry and interest to explore how to develop the batch amounts of Kodachrome which are still left unprocessed--including the shuttle launch materials. But I certainly don't suggest that this is anyone's responsibility or that pressure should be put on any individual or group to engineer such a method--that is contrary to the spirit of APUG. I'm simply suggesting that there is enough experience and talent out there to solve this problem.


    Any non-standard process to develop Kodachrome will have problems. The substitute dye couplers and the dyes which they produce will probably lack saturation, stability and proper hue. Nonetheless they will reveal a color image which is otherwise lost and which might be preserved and corrected using other means; perhaps electronic. This seems a better solution than resorting to mere black and white development--all due respect to B&W photographers.


    The process to develop Kodachrome is notoriously difficult. First the black layer, (the anti halation layer), must be removed by an alkaline wash using a scrub brush of some kind. Then the film must be developed in a black and white developer and stopped--BUT the stop bath must not be too acid as this destroys the sensitizing dyes which make the layers sensitive to blue, green and red light respectively. Then the red layer must be exposed to red light through the base of the film in a manner which exposes all of the undeveloped red sensitive grains--BUT NO OTHER GRAINS such as the ones in the blue and green layers. After red light exposure then develop in cyan developer and stop. The film now has cyan dye in it. Then expose the blue layer to blue light through the front of the film and develop with yellow developer and stop. The film now has cyan and yellow dyes in it. Next use a chemical to expose the green layer and make those grains develop-able; develop with a magenta developer and stop. Finally use Farmers Reducer or something like it--a BLIX-- to wash out the silver and leave only the dye images.


    I only review this process because some people might not be aware of it and because I believe in returning to first principles. Kodak called the developing process K-14 because it had 14 steps to it. Complicated.


    Nonetheless it is not impossible. It seems to me that a lot of people who are expert on processing cannot come forward because they are bound by non-disclosure agreements or similar concerns. This is to be expected and is perfectly proper. No inventory of the processing facilities has been revealed to my knowledge. There may be an unused batch of chemicals out there for all I know. When you come right down to it we are dealing with 1938 technology.


    Time was when Kodak would go out of its way to help the consumer. George Eastman made his reputation by replacing all of the film plates he sold which were contaminated with bad gelatin. The cows from which the gelatin was made had eaten mustard plants and this material caused the photographic plates to fog. Eastman replaced the plates at no charge and hired chemists to get to the root of the problem. Bradford Washburn used Kodachrome to photograph Alaska when the sheet film first came out. But he was given tungsten film and did not use a filter to correct for daylight. Dr. Wesley Hanson worked out a process to correct for the wrong exposure in the lab and many of the images were saved. Can't we recover that helpful spirit? Just saying....

  6. #366

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    Quote Originally Posted by kb3lms View Post
    Great, but that isn't a K-14 coupler. It's just a simple cyan producing coupler. And, by the way, you see the price of that stuff, yes? Now, go get a price on the real thing!

    On the other hand, for small quantities (say 100 rolls worth) you'd probably have to try to DIY it. So, just how DO you make 4-chloro-1-naphthol in your basement? Can it be done? Sure! But HOW is the (rhetorical) question!

    Yes it is very expensive, dont know how much would be required to process a roll, but cant be a huge amount of the chemical required for processing the film, or else the price of processing Kodachrome would have made it obsolete before Kodachrome even got off the ground!
    Its also possible other chemical suppliers can supply it cheaper anyway.
    I can only guess that the Kodak formulation of the coupler can be synthesised from 4-Chloro-1-naphthol as a building block?

  7. #367
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    Quote Originally Posted by Poisson Du Jour View Post
    Wwwwhat!? $250!?


    Come off the glue!

    Other things you can do with an idle $250?
    For me, a KEP-M gallery print, 81cm x61cm, dibonded, mounting battens and certificate, ready for the bright lights of the gallery. All that (including scan, colourimetrics, proofing etc) from film that remains available and abundant and is cheap to process. Kodachrome has gone. Tugging at the forelocks of a carcass is bizarre. Move on with what film you have and what is available.
    Wasn't the same thing said about Polaroid? I was surprised to see Polaroid come back, and would be astonished if Kodachrome could come back even as a niche product.. but since I was so wrong about the demise of Polaroid.. I'll wait and see on Kodachrome.

  8. #368

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    Quote Originally Posted by kb3lms View Post
    On the other hand, for small quantities (say 100 rolls worth) you'd probably have to try to DIY it. So, just how DO you make 4-chloro-1-naphthol in your basement? Can it be done? Sure! But HOW is the (rhetorical) question!
    May I take this opportunity to STRONGLY DISCOURAGE anyone reading this thread from attempting to synthesis any chemical compounds. Not only can it be very dangerous and potentially life threatening but it requires a firm knowledge of organic synthesis and a well equipped laboratory. Something that people do not usually have in their basement. Even a deceptively simple compound can be very difficult to make. As an example I give azulene which is a geometrical isomer of naphthalene a common and readily available chemical.

    http://en.wikipedia.org/wiki/Pfau-Pl...lene_synthesis

    constrast this with the naphthalene structure

    http://en.wikipedia.org/wiki/Naphthalene

    Instead of having two condensed six membered rings it has a five member and a seven member ring. On paper it would seem easy to move the center bond to accomplish this. A simple synthesis which assumes certain special raw materials also be available runs to a dozen steps.

    The more this thread goes on the more it should become plain to everyone that Kodachrome processing is not coming back. There is no motivation or money to make it come back.
    Last edited by Gerald C Koch; 08-26-2013 at 09:40 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  9. #369
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    it requires a firm knowledge of organic synthesis and a well equipped laboratory. Something that people do not usually have in their basement.
    Exactly! You don't just go chemical shopping on eBay and mix up some stuff. This is not simple. Many folks here think emulsion making borders on the impossible yet K-14 has gone on for years! Basic emulsion making is a "walk in the park" compared to K-14.

    As an example I give azulene which is a geometrical isomer of naphthalene. Instead of having two condensed six membered rings it has a five member and a seven member ring. On paper it would seem easy to move the center bond to accomplish this.
    How many of you understand what this means and how you would make it? I don't.

    Now, if someone has the proper training, materials and equipment, I say go for it. All encouragement and the best of luck to you. It WOULD be great to see the remaining films developed in color.

    If you don't know what you are doing this could all go wrong very quickly.

    Kodachrome died off for a reason. Great as it was, and regarded by many as Kodak's flagship product, it WAS 1938 technology. There is just nothing more to see here. Move along.
    All this has happened before, and all this will happen again.

  10. #370
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    Jerry, we worked with Guaiazulene quit a bit in our labs. It is a magenta dye that shifts to cyan in an acid condition. The problem was that we could not stabilize it.

    Organic Chemistry by the untrained is a sure way to shorten your lifespan! I cannot believe this thread.

    PE



 

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