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  1. #31

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    I created and titled the thread when I was still learning what the process was. The film is Svema CND64, which uses a process very similar to ORWO 5166. Whether "CN17" applies to the film or the process is a subtlety that eluded me when I created the thread, and that frankly I don't really care about at this point. I've got film. I've got formulas. They aren't working too well.

    FWIW, I got the idea of putting a snip of leftover leader through fixer without developing it first. I dunked it for seven minutes in the sodium thiosulfate fixer formula I've got. The film snip is still hanging to dry, but the density seems pretty similar to that of the fully processed film. The color's a bit grayer -- the fully processed film has a bit of a magenta cast to it. This suggests to me that the film is supposed to be that dark, at least to my limited understanding -- wouldn't even fogged film clear when dunked in fixer without processing? Some other very old and badly fogged film I've got certainly clears very nicely when fixed without developing. Or might there be some age-related change that could darken the base independently of emulsion darkening effects of age?

    I think I'll try another test roll, doing half in a B&W developer and the other half in bleach bypass. It may be a few more days before I get around to that, though....

  2. #32
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    Just fixing the film will leave the CLS yellow filter layer. It will have a yellow cast.

    PE

  3. #33

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    So the bleach should get rid of that CLS filter layer? The strip I fixed without processing is definitely more gray than yellow, but it's not dry yet. Would Kodak C-41 bleach get rid of this layer, or would a potassium fericyanide fixer be required to do that job? I ask because I used the Kodak bleach for the half of the roll I did with NCF-41, but a potassium fericyanide bleach (with an accidental omission of dipotassium phosphate, as noted earlier) with the other half. Both look similar in terms of base color.

    I'll try running my snip through bleach and then fix it again to see if it clears further....

  4. #34
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    Any bleach will get rid of all silver and should leave clear film after fixation. If you use ferricyanide, there should be a clear and wash afterwards before fixing. In fact, if you use it in a color process, a clear and wash should be used both before and after a ferricyanide bleach.

    PE

  5. #35

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    I've run my pre-fixed film snip through Kodak's C-41 bleach and it cleared from a foggy gray to a pale yellow color in under two minutes, so it's looking like the processed film is indeed very badly fogged. Oh, well. I knew it was a long shot that it'd be usable for anything when I bought it....

  6. #36

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    FWIW, I've run another test roll. Bleach-bypass was a complete bust; there was no visible image (the film was dark) and even my scanner couldn't pull anything off of it. Bleaching and re-fixing produced rather poor images.

    I did have more success, though, by adding a boatload of benzotriazole to the Svema developer formula. ("A boatload" is a highly precise term meaning 5ml of a 1% solution.) The results were much better -- obviously no competition for current films, but more along the lines of what I was hoping to get. Here's a sample shot. Visually, the negatives are thin, with an overall yellowish-orange mask or cast. I'm thinking of extending the development time, cutting the benzotriazole in half, and/or increasing the amount of CD-4 I've used. (I used 4.6g of CD-4, vs. the 2.3g of CD-1 called for in the original formula, so I was thinking of going up to 6-8g of CD-4.) Any thoughts?

  7. #37
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    As you go up in developing agent, the pH may drop!

    Color developers are usually sold as acid salts. So, make sure that pH stays constant or you might actually decrease activity.

    PE

  8. #38

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    Thanks for the tip, PE.

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