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  1. #11
    Bertil's Avatar
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    Good idea Athiril, I just tried, using a razer blade. It looks as if some"flakes" are ON the surface and possible to cut/scraping away (typical on the non-emulsion side!) and some not. The explanation should reasonable be that some "flakes" are "hole" in the emulsion, and some of these emulsion pieces are to be found on the film surface. Sounds reasonable to me, at least.
    (BTW, a frame/sheet with this damage to the emulsion in not totally ruined, at least with scanning and with a quite easy retouching nothing looks wrong; though perhaps not optimal for a regular print.)

    Thank you Athiril for your interest in the issue and very good suggestions (have never experienced this kind of emulsions problems, but your choice of the word "flake" rather than my "spot" really pointed to what seems to be a reasonable solution!)
    /Bertil

  2. #12
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    But if it's true, it's a VERY interesting phenomenon... Modern color films are so well hardened and so robust that I find difficult to damage them! And this kind of damage sounds very peculiar... It really should not have anything to do with too low temperature, or too low rotation speed, or things like that... It has to be something more dramatic, or a serious problem in the film or the chemistry.

    Please keep us updated if you find anything!

  3. #13
    Bertil's Avatar
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    Thank you hrst for your interest in the issue. I will this weekend try to expose some rolls/sheets and be very careful in the processing the first roll in my old chemistry. If everything works Ok I will assume that my earlier treatment was defect, particularly I think my last washing method was too agressive. If i get the same problem, though being very careful, I will mix a new liter C-41 and see If that will solve the problem, in that case it seems reasonable to assume, I think, something is wrong with the old chemistry.
    BTW, in view of my earlier experience of C-41 with agitation quite similar to ordinary B/W development in an ordinary Paterson Tank, and one try with the Jobo machine using the low rotation speed -without any problems! - I felt that the faster speed, especially for development of 8-10 minutes at 30°C, was a kind of exaggerated type of agitation. On the other hand I read the latest Jobo CPE machine (Jobo CPE +) deleted the slower speed as not needed. Well, I don't know. But perhaps you are quite right that modern color emulsion is so robust that what I managed to achieve (!) is very peculiar. I will make a new try and at least go on with the fats speed. I will keep you informed of the results.
    /Bertil
    PS. I scanned with my Epson 4870 several of these ugly looking negatives and several of them was very good without any retouch!! DS

  4. #14

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    Once I had a similiar problem. It turned out that this were actually fine glass flakes from my storage bottles. C-41 Developer is quite alkaline, and the glass of the bottles (cheap one-way beverage bottles, no real labware) was edged by the developer; the flakes stuck to the emulsion during processing and produced a lot of "defects" in the finished negatives.

    Georg

  5. #15
    hrst's Avatar
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    I can't believe that any agitation you can do in a tank could cause this kind of defects.

    Georg's point is interesting. If you can separate the "flakes" off the film using a sharp knife, you can try if they are flexible or not by bending them carefully. I know this won't be easy as they are very small . But this way you could see if they are glass.

  6. #16
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    Finally I think the problem is solved! Something must have happened to my chemistry; no doubt I overreached the 6 weeks which the Tetenal manual says is the durability for used and mixed developer with at least 4-5 weeks; I stored it in brown glass bottles, but the top contained some air and I didn't use some ant-oxidation spray. After some try with this chemistry, changing to the low rotation speed on the Jobo CPE-2, keeping all chemistry and washing water and stabiliser very close to 30°C the result was as disappointing as before.

    I don't doubt that the "flakes" came from damage to the emulsion: at the bottom of the thank after stabiliser a lot of flakes glittering in clear cyan and magenta colour, and no doubt at certain spots something was missing in the emulsion with shapes close to flakes!

    Mixing a new liter chemistry and running this evening two sheets of Ektar 100, the same procedure, temperature and care as above, the sheets came out nice and clean! Very, very satisfying to say the least!!!
    Perhaps the chemistry wasn't just a little bit old, some contamination may perhaps be a better explanation. After all it was just something like a week between my first roll with the Jobo machine, without any problems, and the next developing session that started the "flake" problems. I used tanks and film holders bought second hand on eBay from many different sellers. Perhaps the first lesson is to be very careful with cleaning the stuff before using it; I just used them, they all looked nice and clean, never thought of starting by cleaning everything. Maybe that was the beginning of the problems.
    At the moment I'm quite Happy!!
    /Bertil

  7. #17

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    I still can't imagine why an outdated developer should remove the emulsion in flakes. This simply does not make any sense.
    Try to see it the other way: The developer contains flakes (wherever they might come from). The flakes stick to the emulsion during development, leaving the underlying area undeveloped. Some of them come off at later steps, producing the impression of "holes" in the emulsion (which are in fact just undeveloped areas).
    Ordinary brown glass bottles are (in my experience) not suitable for sorage of C-41 developer (as well as other highly alkaline developers). Use borosilicate glass instead, or PETE plastic bottles (although HD-PE may be okay for a few weeks).

    Georg

  8. #18
    Bertil's Avatar
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    Hello Georg, you may be quite right about what makes sense in this case. I did suspect that some particles in the developer might cause the problem, so before I run the last film in the old developer I filtered it and did find at the bottom of the filter some needle shaped crystals, but not shaped in anything like the "flakes". Using that filtered developer still ended in a lot of "flakes" on the film. I agree outdated developer shouldn't cause this to the emulsion, that's why I suspected that it might be some contamination due to not sufficiently cleaned equipment.

    But after all I'm in fact NOT really happy this morning!! After careful inspecting my last two sheet when completely dry, processed with the newly mixed chemicals, I found 2 small "flakes" on one sheet, and 3 small and 1 quite large on the other!
    I have now followed your advice and changed to to plastic bottles and filtered the chemistry.
    Though we are supposed to have very good water supply in the area, I will probably use distilled water next time I mix the C-41 stuff.
    /Bertil

  9. #19
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    Dear Friends: Good News! I have today developed 4 sheets 4x5" of Ektar 100 WITHOUT any sign of these "flakes"!!
    First, as I said above, I did follow Georg's advise to use plastic bottles rather than glass (I changed for the developer and the bleach fix); I have several times filtered the chemistry; the rest close to what I did before and using the fast rotating speed on the Jobo machine.
    The ONLY THING THAT CHANGED THIS TIME – with the result of NO "flakes" – is that I bought myself a new digital thermometer (Amarell Electronic, quite expensive, I think: $85.00) from the chemistry lab shop at the University, in order to have something Really Reliable about the processing temperature. It turned out that my older thermometer (belonging to the Jobo equipment) showed 1.8°C TO MUCH! Thus, my "problematic flake producing" Tetenal C-41 processing had consistently been performed at too low temperature, perhaps something like 28.2°C (82.76°F) rather than 30°C (86°F)! (Though, obviously, underdeveloped no problem producing OK scans from these "flake negs"!)
    Could this too low processing temperature explain the "flakes"?? (Why no "flakes" on the first Jobo processed film using the same incorrect thermometer that came with the Jobo equipment?)
    Best Regards
    /Bertil

  10. #20
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    No, too low temperature cannot explain the flakes in any way. It is either in developer (from water --- did you use tap water? ---, Tetenal chemicals or from bottle), or you have defective or SERIOUSLY abused film.

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