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  1. #31
    David Lyga's Avatar
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    Greg and all: to explain better: the NEGATIVE (without bleaching) prints as well as one that has been bleached; but PRINTS processed with only fix will, indeed, have more muted colors. Yes the PRINTS need fix after bleach to remove all the halide silver, but not the negs.

    SIWA and Polyglot: either I am really denser than I thought or maybe you did not fully understand what I was saying. First, yes, I FIX before bleaching, both with C-41 negatives and RA-4 color paper. After fixation of the negative (also the print as you know) you are left with ONLY metal silver, not the halides. (I think that we can all agree with that simple fact.) There are no halides to eventually discolor just like with a fully fixed B&W negative there are no halides to discolor. NO silver salts left, right? ONLY silmver METAL. If you leave it at that I think we can all agree that the image (somewhat denser because of the metal silver on top of the dyes) is secure from deterioration (except for possible dye change). Now the difficult part: if I decide to proceed with bleaching the negative I then bleach in potassium ferricyanide. I do not understand why but with negatives ALL the metal silver comes off after about three for four minutes in the bleach (my PF stock = 10g PF per liter). I KNOW that this is not 'supposed' to happen because the bleach is supposed to turn the metal BACK into those darn halides (silver salts). But the silver ALL COMES OFF except for the dyes which are not silver. I have tried this with Fuji Super G ISO 100 as well as other Fuji films and Kodak films. I have tried NOT putting the neg back into the fixer again after this bleach and after it dries after washing there is NO difference between those that are returned to the fix (even for more time!) and those that are simply washed after this bleach. Processing the paper prints, on the other hand, DOES require brief fixation after bleaching and there IS a VISIBLE removal of the haildes as the print gets slightly cleared. (NOTE: after the FIRST fixation you can turn on room lights for both negs and prints and watch, in full room light this ending process.)

    All I am trying to do is impart this so that you can try it. Take a few inches of film and run it through your camera. Use three small cups in the dark and use your fingers (!) to make things easy. Develop as you normally do at your normal temp (I guess this is 100F with C-41 but I also use other temps sometimes and adjust time with not problems). Now, of course in the dark, immerse in stop bath for a few seconds then fix for at least four minutes. Then turn on room light. Rinse negative and pat it damp-dry with a clean tissue (both sides) and hold up to a light bulb and look carefully with a magnifying glass as if you were inspecting a color transparency. You will be a beautiful image with all the color and contrast you expect. It would even be better if you dried the negative with a hair dryer before inspection. (Of course it is somewhat denser because of the layer of METAL silver on top of the dyes but if you were to dry the negative, at this point after washing, it would really not look bad as drying does lesson its density, as you probably know.) AT THIS POINT the negative simply needs washing to be ready for use. But if you wish to go further and remove the METAL silver, then bleach; you will end up with a negative that has NO silver (metal or halide) and, of course, would be somewhat less dense. Cannot be simpler than that. Again, ALL the negative's silver comes off with this bleach but I briefly immerse back into the fix just to put my mind at ease. I scrutinize my negatives VERY closely. There is NO retained silver here, folks. I'll be happy to snail-mail one of my negatives to anyone who wishes to receive one, free of charge. Again, again, for PRINTS you MUST fix again to remove the halides from the bleach. - David Lyga
    Last edited by David Lyga; 07-19-2012 at 11:44 AM. Click to view previous post history.

  2. #32
    hrst's Avatar
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    Quote Originally Posted by David Lyga View Post
    Yes the PRINTS need fix after bleach to remove all the halide silver, but not the negs.
    YES the negs need too, for the very same reason! But it's up to you to not believe it if you don't want to. It is a fact that is quite easy to check, or we can arrange a vote with a few experts hanging around here.

    Again; without fix after bleach, the film will start turning darker when exposed to light.

    First, yes, I FIX before bleaching, both with C-41 negatives and RA-4 color paper. After fixation of the negative (also the print as you know) you are left with ONLY metal silver, not the halides. (I think that we can all agree with that simple fact.)
    This is true.

    There are no halides to eventually discolor
    Yes there are, because: Bleach works by turning metallic silver to silver halides.

    This is exactly the one and only reason why fixer needs to be after the bleach. If it is not, you have halides at those places where there used to be metallic silver.

    Now, there ARE bleaches that actually REMOVE the silver directly without turning it to halides -- namely B/W reversal bleaches such as sulfuric acid dichromate or permanganate bleaches.

    Also, some color bleaches remove SOME silver directly; but still, most is turned to halides, and you NEED a fix to remove them. Otherwise the film slowly turns back to "non-bleached" film.

    Ferricyanide bleach with added bromide is considered a rehal bleach which means that is shouldn't remove any silver directly but turn everything back to silver bromide. But if you add no bromide at all, I don't know what happens! Maybe someone will know. Maybe part of the silver is really removed in the lack of free halide. Maybe this explains your observation. Maybe half of the silver is removed and only half turned to halides, giving a "clear" look to film. It is still hard to believe all the silver would be removed directly.


    I do not understand why but with negatives ALL the metal silver comes off
    What do you mean by "coming off"? How do you see it happening? How can you know whether it "comes off" or just turns into something harder to see (silver halides)?

    This CAN be tested. Working all the time in full roomlight, fully expose a strip of film (B&W should be fine). Partly develop it in a B/W developer by dipping one end to developer, until it is black. Stop, wash, FIX like you do, and wash. Now bleach the whole strip until the black area is gone. Wash and put the whole strip BACK to developer. If there is no silver halide there, nothing will develop. If the bleach has turned the silver back to silver halide like it should, you will get the black bar developed back where it was. This is a simple test.

    There are also test kits for residual silver halide. Have you run one? How can you be so sure that there is no silver halide there without testing? Especially when there really SHOULD be.

    I don't want to sound like a jerk but earlier you have stated that you cannot see any difference between results at different temperatures of C-41 development or your own custom process utilizing RA-4 developer for C-41 film, and when these tests were repeated by others, most of those who replied could see very clear differences. This is why it's hard for me to merely trust your eyes. I'm not saying your attitude would be wrong; quite the opposite, the most important thing is that you are satisfied with your results and use what works for you. You also do a great and important job in showing how robust there products and processes are as they can give perfectly usable results even from horrible "mistreatment". However, I would STILL like to see some more concrete proof to your claims than merely your visual guesstimate; such as residual silver halide test. Because there are many people with very high standards out there.

    Finally -- even if the process you propose worked "well enough" with a few films and processing conditions you have tested, I can't understand why anyone should use such a process that is really "on the edge". Adding a decent fix after the bleach like is normally done does not cost anything, just a few minutes of time; and your process is already taking time so it won't make a big difference. But adding the proper, long enough fix after the bleach will 100% surely ensure that the effect of the bleach won't disappear after processing!
    Last edited by hrst; 07-19-2012 at 08:33 PM. Click to view previous post history.

  3. #33
    David Lyga's Avatar
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    When I am wrong I am wrong. That is what this forum is for: to elucidate the truth and not uphold egos.

    Said SIWA (hrst, all the way from Scandinavia no less): "Bleach works by turning metallic silver to silver halides". SIWA, your dire verbal efforts do manifest into a self-correction of sorts. (I already knew this with theory but it seemed to fall on its face when tested.)

    Last night I burned the midnight oil and did a definitive test in order to prove photo theory (and SIWA) 'wrong' (in this specific instance) and David Lyga correct but was met with at least partial dismay. I developed the negative normally and then put it in stop bath and then full fixation. After fix, at that point we all agree that even without the bleach the existing metal silver was 'safe' to keep on the negative (as with traditional B&W process) as it had turned to metal.

    I then bleached in the potassium ferricyanide (10g / liter stock) and got what I always get: dramatic reduction in density after several minutes in the PF. I then decided that, once and for all, I would make a definitive test to 'prove' that I was correct and I dipped only HALF of the negative back into the original fix for about 20 seconds. I then removed the negative and, as transparent as the negative was after only the bleaching, there really was a slight, vaguely visible 'line of demarcation' between the part of the negative that had received this second fix and the part that had not gotten this second fix. Although the reduction in density was very slight, it was, indeed, measurable and absolutely HAS to be the result of removal of a tiny bit of halide that remained after the silver was halogenated by the bleach. Further fixation past this half minute time did not result in further removal of halides because all the silver was gone after that short time. Indeed, I was wrong and SIWA and others were correct. But....

    Fact is that this second fix resulted in the FINAL removal of halides; one that was definite but difficult to see. I ascribe this to the fact that MOST of the halides had already been removed in the bleach step because the negative was already laden with fixer when immersed into the bleach and that 'fixer presence' was allowing this '90%' removal to happen. But it was not a sufficient amount of fixer to do the job fully. Hence, the NECESSITY to fix again. However, where I do hold my ground here is the time necessary for this second fix: honestly, 30 seconds is sufficient here as there was absolutely NO further reduction with a longer fix.

    I stand technically corrected but hold onto this (30 second) shorter fix time for this final removal of the remaining halides. Thank you all for helping me to further hone this rather simple process. Theoretically, I knew I had to be wrong from the onset because we all know that bleach, alone, does not do the job but merely transforms silver from metal to salts; the deception was in that it surely seemed to do the job fully. Your tenacity forced me to refine what I thought was already definitive and, yes, little as the remaining halides were, they could discolor with age and change the character of the image. The 'slightness' of the remaining silver deceived me because MOST of the silver had been removed in the bleach (because the negative was laden with fixer). However, throwing a monkey wrench into the equation, even if I had rinsed the negative in water, removing the fixer, it STILL would have ALMOST cleared in the bleach. I do not know why this is but re-fix, case closed, it of vital necessity and I now stand corrected. - David Lyga

    NOTA BENE: SIWA, the reason I fix BEFORE bleach is because I always want the option of NOT bleaching. This need can come about if the negative is severely underexposed for some reason and needs the 'backup' of metal silver plus dye in order to slightly enhance the negative's contrast. (Dye plus silver DOES give a slightly more contrasty image.) A negative that has NOT been bleached but is underexposed (hence, of too low contrast) WILL print better than if it had been bleached and refixed, leaving ONLY the dye for the image. - David Lyga
    Last edited by David Lyga; 07-20-2012 at 08:07 AM. Click to view previous post history.

  4. #34
    RPC
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    Thanks for the test and telling us the result. It makes me think of all those out there who use a bleach-fix for their film instead of a separate bleach and fix and think it works just fine. But does it really?

  5. #35
    David Lyga's Avatar
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    I don't know, but even mighty 'photo engineer' has admitted that the blix is both difficult to make for film and has, I believe, inferred that it just might not do the complete job sometimes. I love my method: it is clean, predictable and always repeatable. You do not have to worry about "is the blix sufficiently oxidated?" and other worries. You simply process like for the traditional B&W process and, if you WISH (!!) can continue with the bleach (and re-fix). You have to buy ONLY color developer, as the others are B&W chemicals (assuming that you consider PF to be a B&W chemical, which most do).

    I will state briefly that my developer is from the standard concentrates from Kodak (Flexicolor). But that is where the familiarity stops cold. My dilutions are not for the weak-willed or for people who are terrified that 'it cannot work'. Listen carefully.

    I diute standard Flexicolor developer in this way. FIrst, I buy the large size, 25 US gallon, from PDISUPPLY.COM in Rochester, NY and, yes, they ship and are reasonable.

    That large size has the following volume (I am going to translate from avoirdupois into metric.)
    Part A = 2 X 3784ml = 7568ml
    Part B = 2 X 444ml = 888ml
    Part C = 2 X 473ml = 946ml

    Now, Kodak says that this provides a total of 2 X 12.5 = 25 US gallons. David Lyga says that these concentrates provide twenty times that, or 500 US gallons of working solution. WOW!

    To make only one liter of working solution developer I do the following (keep in mind that 14 drops with my eyedropper equals one ml with these concentrates):

    Start with 900ml of water to which 9ml (yes, measured by volume, not mass) of sodium carbonate, mono, have been mixed in thoroughly. It is important to have this carbonate mixed in thoroughly. In Philadelphia the tap water is hard so I have to either treat it or use distilled or bottled water. Make sure that you get a clear solution; no cloudiness.

    To this 'alkaline water' carefully add 16ml of Part A, then 1.88ml of Part B (not difficult, as this is almost precisely 26 drops from the eyedropper), then 2ml (ie, 28 drops) of Part C. (NOTA BENE: between each concentrate flush out the eyedropper with clean water and make sure that the eyedropper has NO water in it, not even a drop, as you want all the drops to be actual concentrate.) Mix thoroughly, temp not critical here. Add the bit of water needed to make the full 1 liter. You now have what I will call "MY" developer stock. This stock is precisely five times LESS concentrated than Kodak says to use for actual development. In other words, when I make this one liter, Kodak would have said that it should have made only 200ml (1/5 of a liter)!

    Now, "MY" stock is too strong to use for developing the film!!!! For your developer working solution dilute "MY" stock 1 + 3. In other words, one liter of "MY" stock makes four liters of actual working solution developer (tap water is fine for this dilution). Thus, to summarize the math: "MY" stock makes 125 US gallons from the whole kit (5 X 25 US gallon size). Then this 125 gallons of "MY" stock is FURTHER diluted to make actual working solution: 125 US gallons X 4 = 500 US gallons of actual working solution developer.

    Obviously, you do not want to mix huge batches. That is why I told you how to make only one liter of "MY" stock. I believe that smaller sizes of Flexicolor developer (ie, 5 liter or 10 liter) have the same ratios for concentrates, thus you can use my quantities (ie, 16ml, 26 drops, 28 drops) of any size kit to mix your "MY" stock. Keep in mind that you can store these concentrate practically indefinitely if you take the trouble to store them in PET plastic (common clear, brittle soda or juice bottles seen everywhere today; for tiny quantities get 50ml liquor bottles with the metal cap). To keep the volume level up to the very rim (essential to prevent oxidation, folks) you use glass marbles (Walmart). For the tiny liquor bottles I use very small glass marbles (from arts and crafts stores). Either concentrates or "MY" stock can be kept almost indefinitely in this way. Fill to the absolute rim, as there is very little sulfite in color developer.

    Having diluted the "MY" stock to the working solution you are ready to develop the color (or chromogenic C-41 B&W) film. I standardize on 92F (33.33C) because it is so comfortable to keep hands in during the development. I use continuous agitation and use a water bath to do this in. I do NOT use a tempering bath before development but if you do there should be no problem. Make sure you do not reuse this working solution developer, given these amazing dilutions! Start the water bath, and developer, at about 94F (about 34.5C). The drop in temp will be very slight during development, as ambient is only about 15 degrees (F) less. Develop for 12 minutes with constant, gentle agitation. Then stop, then fix (and you know the rest from above). Your negatives will be beautiful.

    I CAN process at the standard 100F (a bit less time, maybe 10 minutes) or even as low as ambient (80F) try about 20 minutes; test. There will be very slight change in the negative color but correctable in printing. I know that this is 'impossible' to most who (like I did way back) shudder at the thought of deviating from the Kodak Bible (Apostasy!) This works, folks, and you do not have to 'rush' to avoid getting a few more seconds as with the 'impossible' 3:15 time mandated by the great yellow father who is analogous to almighty Zeus, himself, in his authoritativeness!

    No thunderbolts. - David Lyga
    Last edited by David Lyga; 07-21-2012 at 09:35 AM. Click to view previous post history.

  6. #36
    Sirius Glass's Avatar
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    With a Jobo processor and tanks processing C41 film is easy. So is slides and black & white film.
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  7. #37
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    I've always wanted to have a bit of a dabble with processing colour film, but it's never been a high enough priority to actually do anything about it. This thread (and the amount of C41 & E6 in my freezer that's just past expiry since I'm too tight to pay for processing!) my has inspired me to give it a go. One query though, and sorry if I've overlooked it in one of the posts here, but would it be a good idea to have different equipment (ie, tanks & reels) kept specifically for each process? I've got two plastic Patterson tanks, a 5x35 and a 2x35 which do all my B&W in 35, 120 & 4x5, would it be a bad idea to use the same gear for colour & b&W? Or is it just a case of making sure everything is washed really well?
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  8. #38
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    No need for separate tools, just rinse well.
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  9. #39
    David Lyga's Avatar
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    Worry not about using the same tanks and reels. Markbarendt speaks the truth. - David Lyga

  10. #40
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    Fantastic to know, thanks guys. I'm waiting on an order of raw chem to be ready to collect, I've seen Tetenal kits at this same place in the past, will have to grab one when I pick this order up.
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