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  1. #11
    Photo Engineer's Avatar
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    EA;

    With reversal films, 100% of the silver must be bleached and fixed, but in C41 only about 50% of the silver must be bleached. In addition, 1/2 of the E6 silver is a negative image and much of the silver is encapsulated in the developed dye clouds. A blix is weaker than a bleach-fix with few exceptions (cf our patent on this). Therefore it is difficult to blix reversal films and get good dmin and good dye purity.

    If there is no formalin in the process, there is no stabilzation of dyes, and if there is no reversal bath (which there is not with a 3 solution process) then you need a light reexposure for good reversal imaging.

    If the blix is packed as a single part, then shelf life becomes an added issue. See posts on APUG for problems with this.

    PE

  2. #12

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    As I recall, the Arista kit uses a fogging color developer (a borane, I think), and the blix is mixed from two bottles.

  3. #13
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    Quote Originally Posted by Photo Engineer View Post
    EA;

    With reversal films, 100% of the silver must be bleached and fixed, but in C41 only about 50% of the silver must be bleached. In addition, 1/2 of the E6 silver is a negative image and much of the silver is encapsulated in the developed dye clouds. A blix is weaker than a bleach-fix with few exceptions (cf our patent on this). Therefore it is difficult to blix reversal films and get good dmin and good dye purity.

    If there is no formalin in the process, there is no stabilzation of dyes, and if there is no reversal bath (which there is not with a 3 solution process) then you need a light reexposure for good reversal imaging.

    If the blix is packed as a single part, then shelf life becomes an added issue. See posts on APUG for problems with this.

    PE

    I just checked the instructions on the Arista E6 kit, and it does not call for light re-exposure.

    Could one extend blix times to try and remove all the silver? Are there any shortcuts/tricks that one could use to circumvent the incomplete silver removal of a 3 solution process?

    So you are saying that while this would work for Ektachrome, it would not have stable/archival colors?
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  4. #14
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    With the use of a borane fogging agent, you can reverse films. Kodak was required to abandon this method due to the acute toxicity of the "TBAB" reversing agent. (Tri-butyl amine borane)

    The TBAB is also not very stable and goes bad quickly after the developer is mixed.

    As for light stability and dark stability, this is still an issue with E6 films which require formalin. C41 films no longer require formalin but the pre-bleach in E6 contains Sodium Formaldehyde Bisulfite adduct, an odorlous compound which decomposes into Formaldehyde and Sodium Bisulfite in the process, and which acts as a stabilzer. See other comments in this thread though.

    As far as I know, extending blix times cannot hurt much, but depending on the quality of the blix, it might help a bit. If this were so, those with problems might try reblixing some of the dark and off color slides to see what happens. Our tests said that that approach was "iffy".

    PE

  5. #15
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    Quote Originally Posted by Photo Engineer View Post
    The TBAB is also not very stable and goes bad quickly after the developer is mixed.

    As for light stability and dark stability, this is still an issue with E6 films which require formalin. C41 films no longer require formalin but the pre-bleach in E6 contains Sodium Formaldehyde Bisulfite adduct, an odorlous compound which decomposes into Formaldehyde and Sodium Bisulfite in the process, and which acts as a stabilzer. See other comments in this thread though.

    As far as I know, extending blix times cannot hurt much, but depending on the quality of the blix, it might help a bit. If this were so, those with problems might try reblixing some of the dark and off color slides to see what happens. Our tests said that that approach was "iffy".

    PE
    Sorry for my questions, I'm sure that they are going to seem a bit ignorant, but that's how we learn, right?

    I really want to try some at home E6 (I looked at the local lab's rate for 4x5 chromes... ouch!), and my wallet likes the fact that I can get the 470ml kit for about 20 bucks from Arista. However, I also want to make sure that process is somewhat archival in the unlikely event that I take a good picture.

    Does the TBAB goes bad due to oxidation?

    So no matter what I do, any Ektachrome processed using either a 3 solution process or a 6 solution process is going to be unstable and go screwed in a few years? Would refrigeration of the processed films help to preserve the colors?

    The slides appear darker because they have too much silver remaining, correct?

    Sorry for thread-jacking, but at least it's on-topic...
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  6. #16

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    Quote Originally Posted by stealthman_1 View Post
    I have just finished bulk processing the equivalent of 23, 36 exposure, 35mm rolls of E6 with the Arista 1 pint kit, recommended capability, 4, 36 exposure rolls, I plan on running another 10 rolls through it with an additional minute of developer time. The results are as good or better than any professional service I could have gotten at 1/10 or less the price. I am switching to the Kodak 5l however for the sole purpose of any incremental quality increase I will pay for, regardless if I can see it or not, especially if it's just cents a roll tacked onto 50 cents. It is peace of mind. I would not hesitate to use the Arista product again though.
    My evaluation of the Unicolor C41 kit is similar if you exclude the God aweful Stabilizer, which is a disaster in my experience. I could have washed the negatives in sewer water and been better off. I surmise this will work better, I've ordered some Final Rinse to replace the stabilizer/muck they include.
    If you develop with no stablizier your slides will not last long. Kodak Final Rinse does contain an anti-fungual agent but my understanding is that is not enough. The Kodak Pre-bleach contains a chemical that turns to formalin- that is really what is protecting the negatives.

  7. #17
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    The Arista kit has no stabilizer? Does that mean the slides processed with it won't last long?
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  8. #18
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    TBAB is a powerful reducing agent and not do much good to human biochemistry along the way. It therefore can undergo a series of reactions that lead to unfortunate side results such as incomplete reversal or skin rashes. Even the new E6 reversal bath (Stannous Chloride) is subject to decomposition with time, but is much more friendly to humans and the environment.

    If the Arista kit is 3 solution that means: First Developer, Color Developer, and Blix. I see no place for Stabilzer in there or whatever else can be included for this purpose. If it is absent (IF < please note) then the slides are going to be subject to more rapid fade or discoloring. If the blix is inadequate, then the slides will suffer from a varying degree of retained silver, primarily in highlight areas (MQ silver is harder to blix IIRC) and this will give muddy highlights.

    There can be some loss of sharpness as you see a negative and positive weak silver image overlay each other and these tend to blur detail and increase grain.

    The effects are multifold and will vary from film to film and with the technique of the processor, age of solution and etc... So you may see a predominance of one effect over another. Bad reversal will also enter into this.

    But, quite a few people report good results. So.... IDK. The finer grained, slower films will blix more easily than the faster, coarse grained, high iodide films.

    PE

  9. #19
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    If needed, I guess I could go back and rebleach the silver in a better bleach, correct?

    If that is the case, preserving the colors is more of an issue. Is the Kodak E-6 Final Rinse like a stabilizer? Should I get it and use it in addition to the Arista 3 solution kit?
    www.EASmithV.com

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  10. #20
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    Quote Originally Posted by EASmithV View Post
    If needed, I guess I could go back and rebleach the silver in a better bleach, correct?

    If that is the case, preserving the colors is more of an issue. Is the Kodak E-6 Final Rinse like a stabilizer? Should I get it and use it in addition to the Arista 3 solution kit?
    You can rebleach provided the dyes will withstand your particular bleach.

    The final rinse contains no formalin AFAIK, and so it does not fully stabilze the E6 dyes. E6 still requires Formaldehyde which is provide in the pre-bleach as noted above. So, you need a formalin bath with Photo Flo 200 to fully protect and rinse the film.

    PE

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