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Photo Forum / Film Photography / Darkroom / November 2004K-14 Oopsies! (yeah, you know in BW chemistry)
Hi- I have a question regarding some "fun" with developing K14process (KP40) in regular BW chemistry. I did an 8 hour development (hey, why not?) in 1/2 tsp rodinal with 1/2 tsp sodium sulfite. Once washed, etc I took the film out of the spool and the emulsion proceeded to run like water down the strip. I know, of course, this isn't the right thing to do but..Out of curiosity, how come the emulsion turned to mush? Thanks! Cheers, -sd http://www.zoom.sh > Hi- > [quoted text clipped - 17 lines] > -sd > http://www.zoom.sh Are you sure this was the emulsion? Kodachrome has a type of anti-halation backing known as Remjet, it also used on some motion picture films. In normal processing its blown off the back of the film with a water spray. When small quantities of film are processed it must be removed by soaking the film in a carbonate solution and then wiping it off. Rodinal is quite alkaline so I think what you are seeing is the Remjet coming off. Try soaking the film in water for a few minutes and swabbing with cotton balls, you may be able to get this stuff off. Kodachrome should develop to a black and white negative image with a yellow cast due to the yellow filter layer which will remain. The filter is made of extremely finely devided silver (colloidal silver) and is normally removed with the silver images during the bleaching step. You might be able to remove it without damaging the image by using the bleach Kodak recommends for removing dichroic fog, which is also composed of colloidal silver. This consistes of fresh film strength rapid fixer with 15 grams per liter of Citric acid added. Bleach it in this but watch it carefully for reduction of the image. The treatment can be repeated. After the bleaching treat the film in Kodak wash aid and wash as directed. You can print from the negatives without removing the filter but you will have to use panchromatic paper such as Kodak Panalure Select because the yellow filter will remove most of the blue light B&W papers are sensitive to. Its possible it may print on variable contrast paper but probably with very low contrast due to the green light exposure.  Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com sd, Glad you had some fun (that's what it is all about!) but here is your problem... Imagine you bought some nice crispy freshly cooked french fries. Now place them in water for eight hours, and see if they have turned to mush...! Photographic emulsion is organic gelatin, basically, and expands/swells on contact with water, but in this form does not dissolve - perfect for film. In prolonged contact with liquid, the emulsion will swell too much, and may strip from the film. Age causes emulsion to be more susceptible to this - never clean a 1920's neg in water ! You can indeed develop new K-14 in B/W dev, just try 15min @ 20degrees C with D-76. Comes out quite well, but high contrast. You will get a very yellow/magenta base which is the yellow filter, this can be carefully bleached with dilute farmers reducer or similar. You will need to wipe and rinse off the remjet backing with a clean damp cloth and running water. Experiment! Dominic Roberts, Process C-22 http://www.processc22.co.uk > Hi- > [quoted text clipped - 13 lines] > -sd > http://www.zoom.sh Cheers Dominic, Actually I do a LOT of extended development. Its not uncommon for me to do 24 hour development using bw film with <10ml of rodinal in a 300ml tank with (what I consider) great results. I think what Richard said it very likely the answer, actually. Upon further inspection of the KP40 "negatives" I can clearly see that the base side of the film is smeared but the emulsion side has clear frame spacing marks on it. The image is so dark that you cannot even pass light through it with a light table. With a 2 million candlepower spot beam, however, I can clearly see that there is a latent image there just waiting to get out. So, in his description about bleaching the film it would make sense that it would bring the image out. So I shall snip off a section and try it out and report back! Thanks for the response. >sd, > [quoted text clipped - 41 lines] >> -sd >> http://www.zoom.sh Cheers, -sd http://www.zoom.sh > Cheers Dominic, > [quoted text clipped - 25 lines] > > Thanks for the response. I would try to get the Remjet off first. Swabbing the back of the film with stock Dektol should work. Rinse it for a few minutes afterward. If the image is really that dark its probably much overdeveloped. This will take a much stronger reducer than the fixer with citric acid to deal with. There are many reducer formulas but Farmer's is probably the safest one to try first. I am not sure Kodak still puts it up in packets, if so that's the easiest way to obtain it. For overdeveloped negatives the two parts of Farmer's are used separately. This tends to reduce the more dense areas faster than the less dense so reduced contrast. When the bleach and hypo are combined it tends to reduce all densities about equally which is more suitable for overexposed negatives. After using either form the film should be refixed in regular fixer and washed. There are other effecgive reducers. I will post formulas for some if desired, but, AFAIK, Kodak Farmer's Reducer is the only one currently available packaged. BTW, this reducer should also remove the yellow filter layer. Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com I tried the previous recipe you recommended and I've had the film in the solution for many hours now and I don't see any bleaching. Still opaque as you could imagine :) Is it too late after the film has dried? I don't use a hardening fixer... Thanks Richard... >> Cheers Dominic, >> [quoted text clipped - 45 lines] >the only one currently available packaged. BTW, this reducer >should also remove the yellow filter layer. Cheers, -sd http://www.zoom.sh >I tried the previous recipe you recommended and I've had >the film in [quoted text clipped - 7 lines] > > Thanks Richard... If you mean the Remjet, I'm not sure but don't think it matters. It _should_ come off in a mildly alkaline solution with a little help by swabbing. If you mean the silver image it should make no difference whatever. Farmer's should work in a few minutes. In fact, it doesn't last very long once mixed. I am not sure I understood right what you have. I read it that the film is very opaque but has clear areas between frames but has some smudged material on the back, is that correct? I am guessing the smudged material is residual Remjet. The film _should_ also still have the yellow filter layer so the clear areas should show at least some yellowish coloring. It is _possible_ this was bleached by the fixing bath if you used an acid _rapid_ fixer. Non-hardining fixing baths can still be acid. Did you use a packaged fixer, if so what kind? If mixed from a formula does it call for any sort of acid? Acid rapid fixing baths have some bleaching property for metallic silver. When neutral or alkaline they do not bleach. Sodium thiosulfate fixing baths can also cause some image bleaching but it takes them hours. Can you try scratching away some of whatever is on the film? Just a small area to tell which side its on. This is very puzzling. Developing Kodachrome to a B&W negative has been done often where the film was of an older type than can be currently processed. Usually, the development is done in D-76. I don't remember the suggested times but there is some info on the web. Try Google to find this. Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com >>I tried the previous recipe you recommended and I've had >>the film in [quoted text clipped - 35 lines] >D-76. I don't remember the suggested times but there is some >info on the web. Try Google to find this. I have done this a lot. If the RemJet has dried, it takes a lot more time soaking in the removal bath: Dektol, Carbonate or reused D-76. The biggest problem is when some of the Remjet has dried on the emulsion side and might be slightly embedded in the upper layer of the film. This needs a lot of soaking and gentle swabbing. You have to look closely to determine if it is finally removed, after first removing the black stuff from the base; mainly to be able to see the specks still on the emulsion side. If you're going to do this again, really rub all the RemJet from both sides of the film when it is in the stop bath. I used my fingers at that point, and it always worked well. Reducer advice is well put. One caveat is to be careful of overuse of mived Farmer's, as the fine detail in the shadows can bleach out very quickly. This is one reason single Solution Farmer's is able to give an increase in contrast. I tisn't so much that it attacks shadows sooner, but rather that there is usually so much more Silver in highlights that the effect of reduction is not seen as soon. Best to use two solution Farmer's first, to get some of the dnse areas near to where you want them, then finish in short repeated immersions in a weak single solutio, while inspecting the results. Try to stop reduction before everything gets to the point that it looks right in the reducing bath, as there are isues with the effect of dry down and cessation of reducing action after removal from the solution. You can very easily over-reduce. Robert Vervoordt, MFA This seems to make sense. When I pulled the film out of the tank (post-wash) the remjet, as I now know it, was drippinng to the floor in a black muck. It also appears to have stained parts of the plastic film reel (presumably from sitting there 8 hours). I see parts of the remjet dried on the emulsion side. I had assumed, perhaps incorrectly that this meant the frame was gone..But no? I'd love to restore some or all of these to something visible or scannable with a negative scanner. Robert thanks for the advice. I will follow your stop-bath advice on the next roll. I guess I find it weird that the remjet will drip off the film after a 20m wash yet it won't come off until there's a little gravity......It needs a little coaxing, no? >I have done this a lot. If the RemJet has dried, it takes a lot more >time soaking in the removal bath: Dektol, Carbonate or reused D-76. [quoted text clipped - 24 lines] > >Robert Vervoordt, MFA Cheers, -sd http://www.zoom.sh >This seems to make sense. When I pulled the film out of the tank >(post-wash) the remjet, as I now know it, was drippinng to the floor [quoted text clipped - 10 lines] >the film after a 20m wash yet it won't come off until there's a little >gravity......It needs a little coaxing, no? Yes it does. Thanks for the thanks. Just keep in mind that the RemJet is only a problem when it is used in a macine processor or when it isn't removed in the wet stage of hand processing, before the wash. When it dries, its a real PITA. Good luck, Dude. I love your various experiments. >>I have done this a lot. If the RemJet has dried, it takes a lot more >>time soaking in the removal bath: Dektol, Carbonate or reused D-76. [quoted text clipped - 28 lines] >-sd >http://www.zoom.sh Robert Vervoordt, MFA Remjet gone- the hard way: After feeling that this Remjet was really pissing me off I left an entire roll of bw processed K14 film in Blank's solution (Farmers?)- 15mg ascorbic acid with 1:9 dilution of fixer (non-hardening). If I had Dektol handy I would have used that instead but anyway.. I pulled the film out last night and took some lint-free thick lens wipes and sure enough I was removing the remjet. It was stuck on there good and took many washes and tugging on the film to get that crap off the base. The image is visible now through the negative and I intend to do a contact print tonight. Thanks Richard, et al..! p.s. does Hydroquinone have any uses that would allow it to be purchased in pure form in local stores? Google says its good for the skin but I'm sure if I go to a store its going to be mixed with something else to make a cream/whatever. Finally, does anyone know what pure Vitamin E does to development? Thanks! >a macine processor or when it isn't removed in the wet stage of hand >processing, before the wash. When it dries, its a real PITA. [quoted text clipped - 35 lines] > >Robert Vervoordt, MFA Cheers, -sd http://www.zoom.sh > Remjet gone- the hard way: > [quoted text clipped - 31 lines] > > Thanks! Hydroquinone has uses in industry in the dying of furs and other areas. It should be available from dealers in photographic chemicals although there are not many of them. AFAIK Vitamin E has no photographic use. Also, be careful of the cult use of Vitamin E, it is toxic in large doses and some of the less sensible recommendations are for near toxic doses. Actual research on mega-dose vitamin intake shows it to be useless. Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com >> Remjet gone- the hard way: >> [quoted text clipped - 40 lines] >near toxic doses. Actual research on mega-dose vitamin >intake shows it to be useless. Got to be careful, there, Richard. Just about all the research showing any negative effect from Vitamin E, as well as studies negating other food components, are done with extracts, components and synthetic versions of these substances. Most of the time such gimmickry will not produce a result up to the standards of the whole substance. Drug companies routinely bury research that doesn't allow them to find a patentable derivative. The recent Vitamin E scare was an especially egregious form of misinformation. The sample was distorted, the results culled from almost ancient studies and the methodologies were flawed in the same ways as I mentioned, above; synthetic forms of the Vitamin that had vastly differing biological effects. That said, I have to agree that Vitamin E has no use in Photochemistry for the Darkroom. It might be uswed in emulsion making, though, as I once heard Agfa was stumped by the failure of a Cashew crop whose oil was unsuitable for their version of a Magenta layer in one of their reversal color products. Go figure. Robert Vervoordt, MFA What overall procedure did you settle on for developing Kodachrome in black and white chemistry (including removing or bleaching)? --travis Richard to answer your question I am using Sprint speed fixer. I believe 1:9 Cheers, -sd http://www.zoom.sh |
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