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 Originally Posted by r-s
Um.... I know I need coffee, but I'm drawing a blank here. You quoted my message, not Ryuji's.
I did a text search of this thread (it's all on one page as I view it), and the first mention of his name turns out to be in your post #30, which cites "The method described above by Ryuji", but there isn't any traffic from him at all above that post, so I am assuming you are referring to something he said in a different thread?
That's what I'd like to see -- his description of the process that I outlined earlier in this thread (which you quoted in your reply in #35, to which I'm replying now).
Can you point me to his description of this process? I've nosed around the forums for a while, but there are only so many hours in a day 
Sorry, that was your message. I misquoted.
It was your post and your process.
PE
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Ok, now that I have gotten myself straightened out, here is the question for r-s.
If the reversal processing of Kodachrome works, then why the ***warning***?
It does work and there is no question about that. We seem to agree.
Now, as for other reversal films. Well, really, all reversal films will go through a reversal process with a NON REHAL bleach to give a reversal image. In fact, any film will.
As for films with CLS layers, they will probably not tolerate the selective reesposure process that r-s advocates due to the lack of speed and spectral discrimination between layers. Now, I admit that this will take experimentation. I believe I did use a conditional on my initial statement, but the probable result is based on over 50 years experience in photography.
My bet is it will not work.
PE
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My question in all this is: Would these non K-14 processes work for someone who exposed an orphaned Kodachrome emulsion intending to develop it traditionally, or would some drastic change in EI and contrast result?
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With a proper development, and no age related problems, the emulsion should give full speed and reasonable fog, however reversal emulsions are designed for higher fog as I mentioned elsewhere. The contrast would be something else again.
Therefore, a reversal B&W process is probably to be preferred. Assuming you mean B&W processing.
Perhaps someone out there has tried it recently and can give us more information on all of this.
PE
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This thread is a little too technically involved for my very small brain, so I require only a simple answer. 
A friend has a roll of K-12 process Kodachrome II from a camera belonging to a late relative, and she'd like me to process it. I can do basic tank processing in B&W chemistry, or C-41. As far as I'm aware, Dwayne's Photo will only process K-14. My question is whether I can obtain a visible, scannable image by developing K-12 process film in B&W chemistry like Rodinal or D-76, like I can with C-41 film.
Thanks in advance for any information!
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The problem you will run into is the yellow filter layer in Kodachrome is made of metallic silver and silver salts (Carey Lea Silver, finely divided metallic silver, and the silver salts, act as a yellow filter).
After first developer (the K14 process ironically uses a phenidone developer, the formula is available, a web search should turn it up for you, I don't have a URL handy, but most likely any decent film developer would work), you will have a black and white image on the three "color" layers, and, probably a very faint B&W image on the yellow filter layer (the silver salts are very fine grain and thus probably extremely slow, I'd guess about as fast as enlarging paper, or, maybe even slower, who knows).
You will also have the metallic silver from the yellow filter layer. The result is that you will have a dark overall "fog" -- separate from the actual image -- in the yellow filter layer.
I think some people subject the film to a brief bleach step, to remove the yellow layer (or more correctly, to turn it back to silver salts). However, it's IMPOSSIBLE to do this and NOT affect the REAL image layers too. However brief, if it's strong enough to bleach ANY silver, it WILL attack your shadow detail.
Thus, the favored approach is reversal processing, which CAN neatly remove the silver from the yellow filter layer and NOT attack the actual image.
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Okay, so does this mean I would have much better luck trying to process the film with E-6 chemistry instead of B&W?
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E6 chemistry used on Kodachrome will give blank clear film.
PE
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