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  1. #21

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    B/W reversal processing has gone quiet for a while, but I finally got around to having another attempt and thought I'd report on the results, especially as they were a little disappointing compared to last time. I thought I had the process sorted, but apparently not!
    I exposed FP4, as before, at 25ASA. First development was in Rodinal 1+25 for 11 mins at 20 degs C, no hypo, as before. Permanganate bleach 5 mins, clearing bath, re-exposure to light 3 mins each side of the reel 1 ft from a 100W bulb. Develop 3 1/2 mins in Ilford Multigrade, all as before, with all the associated washes and stops along the way. However, the results were rather dark and had a sepia tinge. (The leader was perfectly clear).
    As far as I'm aware, I did nothing different to the previous time, when I achieved quite good results, but from this it looks as if to obtain lighter negs I'll have to have a longer first development time and to ensure that I don't get the sepia effect probably increase the clearing bath time. I may try re-soaking the negs in clearing bath, even though they are now dry.
    A couple of points came up:
    Firstly, I made up a gallon of water at 20 degs C before starting and just used it as required - you get through a lot of water in this process!
    Secondly, I wore old clothes, as splashes of permanganate make a brown mess that's impossible to shift.
    Thirdly, when I first hung up the neg strip to dry I almost didn't bother, as they looked VERY dark, but they did appear lighter as they dried, so don't draw any conclusions until the film is totally dry.
    Finally, instead of using a table lamp for re-exposure as I did before, I relied on the room's ceiling lamp. Not a good idea. After six minutes of standing there like the Statue of Liberty, most of the surplus water had drained from the film and made its way down my upstretched arm.
    Hope some of those notes are of interest. Helpful comments welcomed!
    Best wishes,
    Steve

  2. #22
    John Austin's Avatar
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    These are the rules


    Reversal processing of Ultrafine X 100 in a mix of Ilford Applicaton Sheet Reversal Processing Sept' 2003* and Kodak Professional Data Book J-1 p80 with the addition of ID36 developer from the Ilford Manual of Photography 1971 and reference to British Journal of Photography Almanac 1954

    Ultrafine X 100 bulk roll film is used because it is the cheapest film I can find

    Cookery Book

    ID36
    Metol
    3g
    Sodium sulphite anhd
    50g
    Hydroquinnone
    12g
    Sodium carbonate anhd
    60g
    Pot bromide
    4g
    Water to
    1000ml

    For use the developer is diluted and Hypo, Sodium thiosulphite added. This developer is retained for the second development

    Kodak Bleach R-9
    Water
    1000ml
    Potassium dichromate
    9.5g
    Conc' Sulphuric acid
    12ml

    I use this Kodak bath as the Ilford permanganate bath sometimes softens the emulsion to the point where it washes off the backing

    Kodak Clearing Bath CB-1
    Sodium sulphite
    90g
    Water to
    1000ml

    Alternative sepia toner fogging and redevelopment bath
    Sodium sulphide
    50g
    Water to
    1000ml

    Exposure
    By some odd quirk I found the best ASA setting to be the 100asa marked on the Ultrafine film box, but note that exposure is critical as there is no option for correction with printing paper grades or exposure
    First development
    Like exposure, development time and hypo addition will have to be fine tuned after your first test roll
    First development for my darkroom is 12 mins 20°C in ID36 1+3 water plus 6g/Ltr of Hypo, Sodium thiosulphite
    Retain the first developer bath for the second development
    Stop – wash
    Ilford recommend a 2 minute wash in running water at 20°C
    Bleach
    Use Bleaching bath for 6 minutes at 20°C. Use continuous gentle agitation. After about 30 seconds the lid of the tank may be removed and the rest of the process continued in normal room light. During this process all of the reduced silver should be dissolved out of the emulsion
    Second wash
    Second wash as first wash but continue until almost all of the orange colour has been removed
    Clearing bath
    2 minutes with gentle agitation, the emulsion at this stage is very vulnerable to surface damage
    Third wash
    Two minutes gentle but thorough washing
    Fogging exposure for ID36 development
    Expose the film for at least 1 minute about 1 meter away from a 60w tungsten lamp. An alternative is to use transparent reels and expose the film under water in the dev' tank, but give a bit longer in this case
    Second development
    2 minutes in the saved ID36 plus Hypo
    Fixing and hardening
    Ilford recommend fixing the film, but I do not see the point in this unless a hardening fixer is used. I use a Ilford Hypam Hardener at normal strength, but without the fixer
    Alternative second development using Sodium sulphide
    Re-develop in Sodium sulphide sepia toner bath for 2 minutes. I have read that Kodak odourless sepia toner will work, but for me it did not. The bottle of sepia toner used was purchased fresh in 1981. When using sepia toner second development the fogging exposure in not necessary
    Wash and dry
    Wash with a gentle flow of water for 20 minutes. Remove film from reel with great care and hang to dry without wiping or using a squeege, if necessary use a wetting agent

    Notes,
    1. This is the process I have found works well with the Ultrafine film, however, tests will have to be done and if your images float into the the final wash water start all over again
    2. Sodium sulphite is used as the clearing bath with Pot dichromate, for Pot permanganate bleach use the original Ilford Sodium metabisulphte bath
    3. The sepia toner redevelopment is an alternative to the original Ilford redevelopment process and obviates the need for a fogging exposure, I offer this as an easier alternative. The disadvantage of this process is that as it lacks the hypo added to the ID36 developer which helps to keep the highlight clear, so sepia toned slides are slightly veiled
    4. Kodak also offer an alternative to re-exposing the film, but this uses stuff I have never seen or ever read about before so is probably not in your normal photo-chemical suppliers catalogue

  3. #23

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    I second (or third) the recommendations to try Potassium Dichromate instead of Permanganate in the bleach. (I got my dichromate from Artcraft I believe). Yes it is more toxic but no less safe for the user if you follow good cleanliness practice (Rubber gloves/dust mask when mixing). Dichromate has been the industry standard up until about 10 years ago when Kodak changed their motion picture reversal films to work with Permanganate. It was an environmental move, and given the quantities used in motion picture labs, was a good idea. But for the home user mixing small quantities, if you're concerned, you can render it inert before you dispose of it down the drain by adding a little sodium sulfite.

    Sulfuric Acid is super easy to obtain any auto parts store carries battery acid which is (I believe) a 33% solution. Just alter your formula accordingly.

    I've developed much motion picture film and the one thing that is missing here is you need an EXTREMELY active first developer! Something that is contrasty beyond D-19 and beyond Dektol. The key is to use Sodium Hydroxide as the accelerator (Red-Devil lye, aka crystal Drano--ironically much easier to get than Sodium Carbonate). Always add the lye to COLD water! Never add water (esp. hot) water--to the powder--the results can be explosive!

    I'd do a search for "Kodak D-94" should yield the correct formula for making 1 liter of working solution.

    A couple other hints--once you finish the bleaching step, wash with running water until no more red comes out, then put in the sodium sulfite clearing bath. I use the clearing bath one-shot, just a teaspoon or so (strength is not so important.) During the clearing bath is when you do your light re-exposure. VERY IMPORTANT: After clearing bath, DO NOT WASH again--go directly into the 2nd developer. ANY Washing after clearing bath will strip the emulsion right off with some films. The second developer can be identical to the first, minus the thiocyanate. This will give you maximum d-max.

    Keep in mind, as the other poster said, certain films will just not reverse well, no matter what you do. You need to choose films that have a very clear base and this usually means very slow emulsions. When I was processing movie film, neither FP4 or Kodak Plus-X negative reversed well at all. If I were going to do it with still film I'd try document films, or something like Adox/Efke KB 25 to start.

    Lastly--have fun! Nothing more beautiful than a projected slide.

  4. #24

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    Couple other things, about the light re-exposure--this is a process to completion. No need to take the film off the reels. I'd say 2 minutes under normal room light should be sufficient. I've never "under" done the light re-exposure. Just think, it's virtually the length of time it would take completely expose a negative beyond recognition--not much light needed at all.

    The reason you don't wash after the clearing bath is that the sodium sulfite "prepares" the emulsion by creating an intermediate, slightly alkaline solution to lessen the shock of going into the super-alkaline 2nd developer after the extreme acid of the bleach. The sodium sulfite that remains on the emulsion is insignificant and won't alter the developer since it has sulfite in it anyway.

    To be more specific about formulae:

    D-94 is the original reversal formula with Dichromate bleach

    D-94a is the new one with Permanganate bleach and a substitute for thiocyante called DTOD--(probably a Kodak proprietary chemical)
    Last edited by bluesun267; 03-26-2012 at 01:52 PM. Click to view previous post history.

  5. #25

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    Quote Originally Posted by bluesun267 View Post
    VERY IMPORTANT: After clearing bath, DO NOT WASH again--go directly into the 2nd developer. ANY Washing after clearing bath will strip the emulsion right off with some films.
    I 've just done that with a super8 plusx and the whole emulsion seems to have disolved in the second developer. I used Agfa Neutol NE as developer. I have never experienced the same thing with other films. Is there a more detailed explanation?

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