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  1. #1

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    Replenishing specific E-6 Developer chemicals that go bad

    I'm not GREAT at chemistry, but it occurred to me that within... for example the 3 bath kits, there's multiple chemicals. In each bath.

    Not ALL the chemicals within each bath may go bad right? Only some?

    So is it possible, say I own a 1 L kit, my first developer goes bad after... 12 rolls but it goes bad from TIME ... I did 12 rolls, now it sat in my basement for 3 months, the color developer and bleach are probably good right but the first developer is bad? (Correct me on which goes bad first if I'm wrong, I tend to forget these things or mix them up).

    So if I own certain powder chemicals, could I pour in some of those to reactivate the first developer? Since some of the stuff in there is good it's just certain parts of the mix that go bad?






    ~Stone

    Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk

  2. #2

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    Hi, I'd be more inclined to think the color developer would go bad first, because color developers use relatively small amounts of "preservative". But I don't know my way around E-6, only the color neg/paper processes.

    Still, I'm sure you COULD reconstitute the bad developer, the only problem is in knowing what to add. Most of the time it's probably not worth the effort. I've done this sort of thing in the photofinishing industry, where it's been cost-effective. But for a hobbyist, I'm very skeptical that it would have any real savings.

    If you want to get more life out of your solutions, it would probably be better to use an actual replenisher solution, periodically adding some of this to your used solution. The replenisher is formulated to make up for the specific chemical components that do get used up, at least in a normal processing cycle. For "old" chemicals, replenisher is not ideal, but it should "sort of" work. Best would be a special type of replenisher intended for "low processor utilization."

    BTW, the normal industry terminology for these things is: the solution in the tank used for processing is called "tank solution" (what most photogs call developer, etc.). The solution you add periodically during processing, as a "boost," is called "replenisher" (the replenisher is designed to maintain all the chemical components in the processing tank at the spec concentration). And finally, for the surplus solution (as a result of adding replenisher) that can be reconstituted and reused, sometimes "regenerator" mixes are available; these essentially convert that used chemical back to replenisher. (Other treatments, such as silver recovery, are generally necessary before regenerating a processing solution).

  3. #3

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    While replenishing a color processing system is possible the complexity of the tests required is beyond that of most users. You would need an extensive knowledge of chemistry and an analytical laboraty at your disposal. Kodak used to publish simple corrections such as if a test strip is 10CC too yellow then add x ml of Y per gallon of Z. These instructions were intended for photo labs
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

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  4. #4

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    Quote Originally Posted by Gerald C Koch View Post
    While replenishing a color processing system is possible the complexity of the tests required is beyond that of most users. You would need an extensive knowledge of chemistry and an analytical laboraty at your disposal.
    Hi Gerald, not so...virtually all of the mini-labs, etc, replenish, without much technical expertise. All that's needed is a spec for how much to use for a given amount of processed material, with periodic checks, such as process control strips and maybe specific gravity checks. The specified pH adjustments you mention are a bit tricker, but still at a techician level.

    It mainly gets tricky when one desires to REGENERATE chemicals. That is when the chemical analysis and knowledge of formulas, etc., becomes necessary. My experience is largely in working with such operations having a staff chemist. (Obviously there has to be enough processing volume to be worthwhile.)

  5. #5

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    Replenishing specific E-6 Developer chemicals that go bad

    Hmm, well remember I'm talking about TIME issues, see, the 3 bath kits have calculations for re-use, which in the kit I use is a multiple of 1.04 of the current time.. ie. if the time is 6:30 for the first process, the second run time is 6:45 etc. only for the first developer, the color and blix times stay the same.

    You can get about 20 relatively consistent rolls of 120 from these times with a 1L kit in a 2 reel (of 120 or 3 reel of 35mm) Paterson tank if you do all of them the same day you can get more without too much color/exposure issues.

    But what I'm talking about is time... Say I only have 4 rolls of E-6... I mix up the batch, do my two developing runs, then put the chemicals in the basement and a month later I want to do 2 more rolls. Well the developer has been sitting and oxygen has done SOMETHING to it to make it not good anymore even though I never "exhausted" it with developing. SO I'm saying, perhaps there's SOME good chemicals and SOME bad, and perhaps someone knows which are the ones affected by oxygen vs the ones affected by developing rolls of film, and I can simply add the chemistry that gets messed up by the oxygen/time issue?

    Am I totally off the ball?


    ~Stone

    Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk

  6. #6

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    Yes, minilab s were able to replenish their systems to a limited extent because Kodak did the work for them as I mentioned. If a test strip was too yellow then Kodak determined that you should do this, if it were too magenta then do this. This of course is not what the OP was asking which is more extensive.

    I shouldn't have mentioned Kodak at all as it has diverted the thread from the original question.
    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

  7. #7

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    Quote Originally Posted by StoneNYC View Post
    Am I totally off the ball?
    I have to say yes, what you ask is very involved. Even with degrees in chemistry I would not attempt it. Then there is the question would you save any money.
    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

  8. #8
    Kevin Caulfield's Avatar
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    Quote Originally Posted by Gerald C Koch View Post
    I have to say yes, what you ask is very involved. Even with degrees in chemistry I would not attempt it. Then there is the question would you save any money.
    Likewise, I have a Ph D in Chemistry, and would not even attempt it. It is a bit like trying to unmix a cake after it is baked.

  9. #9

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    Quote Originally Posted by StoneNYC View Post
    But what I'm talking about is time... Say I only have 4 rolls of E-6... I mix up the batch, do my two developing runs, then put the chemicals in the basement and a month later I want to do 2 more rolls. Well the developer has been sitting and oxygen has done SOMETHING to it to make it not good anymore even though I never "exhausted" it with developing. SO I'm saying, perhaps there's SOME good chemicals and SOME bad, and perhaps someone knows which are the ones affected by oxygen vs the ones affected by developing rolls of film, and I can simply add the chemistry that gets messed up by the oxygen/time issue?

    Am I totally off the ball?
    No, you're not (entirely) off the ball.

    Let me reiterate that I have no experience with E-6, which is what you are asking about. I have SUBSTANTIAL experience with the color neg/paper processes, which are fundamentally similar to your color developer.

    Here's what fundamentally happens to color developers: 1) when you develop film: you build up by-products, mainly DIRs and various halides, which may tend to slow down development, and 2) from just sitting, somewhat exposed to air: the preservative package is somewhat degraded, perhaps a small amount of developing agent is oxidized, there is some evaporation, and probably a slight pH shift.

    In the case of E-6, color developer follows another solution, so there is additionally a substantial dilution of tank components due to the carry-in from the film, which does not normally happen with the color neg systems.

    Replenisher counteracts ALL of these things, but the proportions are exactly correct only for one specific aim condition. If you are developing film, with only slight exposure to air, the replenisher should be very close to ideal. If you have a lot of down time, with air exposure, things go slightly off-kilter - you lose mainly preservatives, and slightly developing agent; adding replen gives both. You need to add some volume to counter the evaporation and dilute the byproducts, but replen will tend to overdo the developing agent. So you might try half water and half replen - I'd say this is a pretty fair guess. Processing a control strip will let you know if you're close or not. If you could find a replen designed for low process utilization, it would be similar to the latter, except that it would not overdo the developing agent so much.

    Regarding the question, "is this worth doing?" I don't know. If you're buying your chems in the form of replenisher and using "starter solution," then you already have replen - in this case, likely worthwhile. (You also have to take on the additional job of verifying that the process level is ok.) If you don't already have replenishers, likely not worthwhile.

    I don't know if you'll believe this, seeing as how a couple of hi-level chemists are taking a contrary view. So if you need me to argue with them, let me know. I'm not even a chemist, but my real-world processing experience (outside of E-6) is very substantial. I've overseen setup and operation of developer regeneration equipment for EP-2, using ion-exchange columns to remove bromide, with full chemical analysis to determine the regen formulas (from components), bleach-fix regeneration systems with silver recovery with custom regeneration formulas, etc. So I have a good sense of how these things vary in different operating situations.
    Last edited by Mr Bill; 04-14-2013 at 03:08 AM. Click to view previous post history.

  10. #10
    Kevin Caulfield's Avatar
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    Real world experience is pretty valid, so I'm not arguing with Mr Bill. He makes some very good points.

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