B/W Reversal disaster

Discussion in 'B&W: Film, Paper, Chemistry' started by alxsav, Jun 17, 2010.

  1. alxsav

    alxsav Member

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    Today I tried to mix my own chemicals for bw reversal and tried it to process a roll of Rollei Retro 100 (the one that it is supposed to be identical to Agfa APX100 -and it seems to be).
    I tried a variation of the Ilford reversal recipe using rodinal 1+10 instead of their paper developer and a potassium permanganate bleach.
    Until now I had used the Foma reversal kit which seems to be very similar with very good results both on Fomapan R and Agfa scala.
    Well, the film came almost transparent, the emulsion was extremely soft and it was like it was about to melt.
    The leader of the film was crystal clear as it should be but the unexposed parts (between frames and above the sprockets) were clear too but covered with the soft emulsion instead of being black.
    I first noticed that something was wrong at the light exposure step when I realised that the film wasn't milk white coloured as it should but similar with a normal processed negative. Still, there was some image on it (I cannot recall if it was negative of positive, negative probably). After I fixed the film (with my normal tetenal thiosulfate fixer) it was almost transparent with some very weak positive picture on the soft emulsion.
    A total disaster!
    I suspect that the 7gr sodium thiosulfate crystals I added in the 600ml first developer (rodinal 1+10) were too much or that the bleaching time was too long (5min) but still I cannot figure out what went wrong. Any ideas?
     
  2. hrst

    hrst Member

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    Too clear film / no image -> probably too much thiosulfate in FD. I made my first reversal experiment with Ilford recipe and Agfa APX 100 and got completely clear film. I removed all the thiosulfate and got a usable image. Maybe you should start without thiosulfate and start adding it very carefully (0.7 g instead of 7 g, or so!) if the highlights are not clear enough or contrast is too low. I used Neutol NE as developers, bleach and clearing bath per Ilford recipe and Agefix as fixer at the end of the process.

    I had no problem with emulsion, running APX100 at 24 Celsius. Paper emulsion went very soft, though. Try to reduce temperature a bit and agitate more gently, and use a hardening fixer if available.
     
  3. Existing Light

    Existing Light Member

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    I've been playing around with black and white reversal processing recently, but havent had that problem yet. I use a potassium permanganate and sodium bisulfate bleach for five minutes with constant agitation followed by three minutes of constant agitation in a sodium metabisulfite clearing bath. That does make the emulsion soft, but I really havent had a problem with it so far except for a few scratches caused by my fingernails.

    The developer I use is Dektol 1:2 (paper stringth) for 12 minutes with constant agitation at 68 degrees with no thiosulfate, and I dont see a problem with the highlights. I dont know if the the fogging of the highlights is an overstated problem or if using paper strength Dektol is increasing contrast and counteracting any highlight fogging. At the moment, i'm kinda leaning toward it's an overstated problem because I have no problem overexposing my film and having perfectly clear highlights (And i've dont that in quite a few frames so far :D ). I'd say try again using no thiosulfate just to see how the film looks. If you think the highlights are foggy, add a little thiosulfate each time you develop until you're happy with the highlights.

    I use Ilford FP4+ and Arista.edu 200. I've learned that my EI for FP4 is about 32 and 50 for Arista.edu 200. I dont know about your film, though. Perhaps do some bracketing and find your personal EI. that might help the highlights a little (Maybe. I'm not really sure. I've only been doing reversal processing sporadically for the last few months, so I'm no expert :smile: )
     
  4. jforney

    jforney Member

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    Nothing against DIY at all. Have you considered DR5?

    I am a paying customer. David is a great guy. No financial incentive in my recommendation.
     
  5. Existing Light

    Existing Light Member

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    I'd recommend DR5, as well, but I've never sent in any film to be processed. I've heard and seen lots of good stuff about David Woods' process.It might be good for us both to send in a roll to see how a pro lab processes a roll and compare it to our own processes. I've personally been wanting to send in at least one roll for a while, but I've been too caught up in my experimenting to spare a roll. Now that i've got my process down, though, I'd like to give DR5 a go. :smile:

    I would offer to process a roll of your film myself, but our processes are so similar that I dont think I could process your film any better than you could. I think I might try paper developer if I were you, because I've learned through my own experimenting that the developer needs to be fairly strong.
     
  6. Alessandro Serrao

    Alessandro Serrao Member

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    alxsav try to use half strength permanganate bleach, halves only the permanganate part, not the sulfuric acid.
    Then reduce the overall amount of silver solvent in the first developer and try to conduct your development at exactly 18°C.
    Use an hardening fixer is paramount.
    I'd also use Kodak D-19 as the developer, not Rodinal and do the trials on 3/4 frames max not on the entire roll, this way it's much more cheaper.
    Keep posting results, it's extremely interesting.

    It's generally good to uprate the film if you'll going to use hypo in FD.
     
  7. alxsav

    alxsav Member

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    @jforney, I 've have tried DR5 once, the results were ok but since then I 've got excellent results with the foma kit and my own processing. On the other hand, as I live in Greece, postage and turnaround time is quite an issue to me.
    @Alessandro Serrao, I tried rodinal since it is used by Jens Osbahr http://home.snafu.de/jens.osbahr/photography/reversal_processing/osbahr_reversal.pdf and I had it available. I will try today with Neutol, no thiosulfate in FD and half the permanganate in BLEACH. I will also reduce the bleaching time to 3min from 5min. Do you think to continue using Rollei Retro 100 or switch to an ilford film (I 've got PANF and DELTA100 available)?
    Anyway, I will try again and I will report the results. And a question: Has anybody, ever, used exactly the Ilford process and got good results? I 've only got emulsion jelly spread on the film base.
     
  8. vencahaus

    vencahaus Member

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    There is one problem with BW reversal that has not been stressed enough.

    Every film is unique and requires "unique" process. That means you cannot take one procedure from the internet and apply it on every film. Some films have very thin layer and do not require halide solvent (especially more sensitive films) and some do (especially low-speed films). I believe dr5 is just perfectly calibrated process for every kind of film separately.

    Moreover, some films are more suitable while some are less. I recommend reading film overview on dr5 website to get some starting point.

    There will be fomapan r 100 in 120 format, so if this is the problem why you experiment with APX, I suggest to wait few months.

    Otherwise, I would begin with films already tested, like Ilford HP5+ and so. There is a very good "recipe" by Jens Osbahr that uses bleach based on permanganate. You don't have to use rodinal like he does. I was very succesfull with PQ developer in Foma kit. To be complete, HP5+ in 1+10 fomadon lqr (included in the kit) for 15min, without solvent, constant agitation. I used dichromate bleach however.
     
  9. Existing Light

    Existing Light Member

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    I've never used the Rollei Retro 11, but I dont know why you wouldnt get good llford says PanF as a slide is very contrasty. I believe Ilford says PAn F is best for copying text (black text on a white background), but you might could use it in very low contrast scenes.

    I cant look at the ilford PDF atm because it's not wanting to load on my computer. I have a printout of it somewhere that I cant seem to find :sad:



    I only used it as a guide. Here's my process


    1) Dektol 1:2 @ 20C/68F for 12 minutes with constant agitation for 12 minutes.

    Ilford Recommends their developers, but I dont have any in stock here, but I always have Dektol (And it's easier for me to store bags in my limited space than bottles, so I use powder whenever possible). I found the developing time and agitation recommended by ilford made my film a bit dark, so I went with constant agitation for 12 minutes.

    2) I cant get my hands on sulphuric acid, so their recommended bleach is out of the question for me. I mix a two-part bleach: Part A is Potassium Permanganate and distilled water; Part B is Sodium Bisulfate and distilled water. I bleach for five minutes with constant agitation (which I believe is Ilford's Reccomendation).

    3)Sodium metabisulfate clearing bath. I dont remember what Ilford's clearing bath is. I do constant agitiation for 3 minutes

    4) Re-expose to light: 1 min to 1 1/2 min 16-20inches away from a 100-watt light bulb. I think that's close to the ilford recommendation

    5) Redevelop: Dektol 1:2 for 4 minutes. It's done to completion, so as long as you develop the film fully, the time really doesnt matter, IME. I wouldnt leave the film in there for an hour, but a little over 4 wont hurt, I dont think. I'm not sure with how little you can get away with, though, so I wouldnt go with less than 4 unless someone has a reason not to :smile:

    6) Fix. I use TF5 and use their fixing time and agitation. I dont have the bottle with me, and I cant remember the fix time/agitation off the top of my head.

    I've read in a few sites that fixing is optional since the last bit of silver left in the emulsion after bleaching should be developed completely. You probably should fix, though, in case there's a bit of undeveloped silver left in the emulsion, though

    7) Final wash: Ilford method

    8) Dry

    9)Mount

    10) Enjoy :D





    I do have a wash step between all the steps. I use distilled water at 20C/68F. I fill the tank up, agitate a bit, then dump in to an empty distilled water jug (They come in gallon sizes here in the States. I dont know what size bottles are avaliable in Greece). I take my used chems and washwater to the hazardous waste dropoff. Here in Decatur, Alabama, they do a collection once a month. I save up for a few months then take a truckload for them to take care of

    Good luck with your process. I hope it works out better in the future


    Edit: I also use a stop bath after each develop step. You might can get away with water, but I have so much stop bath at the moment that I dont care if I'm exhausting it more quickly than I should :smile:

    Also, I've noticed that I get a two stop loss of speed with my process. That's not a problem because I have a tripod and my Pentax's have fast lenses. I'm not sure how to get more speed out if the film. Perhaps someone more experienced can chime in (I'm still a bit of a newbie, and I dont claim to be an expert. I'm just posting what I've found to work) :smile:
     
    Last edited by a moderator: Jun 18, 2010
  10. alxsav

    alxsav Member

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    Second try, second failure though a educative one.
    I keep on using Rollei Retro 100 (aka agfa apx100). I used Agfa Neutol WA 1+7 without any hypo and I skipped the CLEANING (POTASSIUM METABISULPHITE+water) step. For the second developer I used the first bath again (in Foma style).
    When I opened the tank after bleach to expose the film, it had the usual "creamy" character though on the yellow/brown side (no cleaning?) The image was clearly visible. Then I exposed the film the usual way (Foma style again) by moving the reel near a 100w bulb for about a minute on each side of the reel. Then I made the Second Development step and after that I looked again at the film and I was almost ok though it still had that "creamy" character more on the brown side. Success I thought until I poured the fixer and the image was gone. The fixer (tetenal) washed the most of the image and left the clear base.
    I assume that since there were image before fixing, that image consisted mainly by the unexposed emulsion that left after bleaching. It should have been exposed and developed. I suspect that the exposure to light was not enough (I don't think that the developer was exhausted after just one film and this was Neutol 1+7, quite strong). The start of the film which was on the top of the reel received more light and it was more black.
    I exposed for around 2 minutes like I did a lot of times with Fomapan R and Scala.
    How much time should I expose next time? Lets say 5 minutes? I think that overexposure is not critical but are there any limits? Exposure with the film on the reel isn't the best but on the other hand messing with 1,5m wet film is not convenient and since I have seen it work a lot of times why shouldn't work now.
     
  11. Alessandro Serrao

    Alessandro Serrao Member

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    Why you skipped the clearing bath step?
    This what happened: skipping the clearing bath has allowed the "main" image to superimpose to the "second" reversal image. What you have done is: re-exposure of the bleached "main" image, developed it (which obviously would not work on a bleached image), then fixed it AND the "reversal" image below it, which was not re-exposured nor developed, so the fixer washed away ALL "main" and "reversal" image.

    Think of the "reversal" image as being physically buried below the "main" image.
     
  12. Alessandro Serrao

    Alessandro Serrao Member

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    Take into account that Agfa Apx-100 in the reversal process has an inherently low Dmax, which yield very flat images. This finding is consistent with David Wood (Dr5)'s finding on his very own process, meaning that Apx-100 is unsuitable (at least to me) to being reversed.
    However keep trying...
     
  13. Alessandro Serrao

    Alessandro Serrao Member

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    The re-exposure is perfectly fine also done with the film on the reels. make sure you expose all the reel at no more that 5/10cm from the bulb for 2 minutes each side, not splattering water on it or it will probably shatter.

    Use an hardening fixer.
     
  14. Alessandro Serrao

    Alessandro Serrao Member

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    If you don't use an hypo solvent in the first developer you'll possibly get a reduced speed to begin with, 1 or 2 stops loss.
     
  15. Existing Light

    Existing Light Member

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    the lack of a solvent in the first developer causes the speed loss? I never knew that. I thought it was just to keep the highlights from being foggy.
     
  16. Alessandro Serrao

    Alessandro Serrao Member

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    But if you think it's the other face of the same coin!
    :smile:
    Put it in another way, the presence of hypo cause a speed gain...
     
  17. vencahaus

    vencahaus Member

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    Do you find pieces of emulsions in the fixer? If you do, there is a problem with bleaching. I would decrease the amount of permanganate. This type of bleach is not very user-friendly. Try dichromate belach if you can.

    I recommend to stop trying developing film that even pro lab (dr5) has difficulties with.

    I also think the relation speed vs. halide solvent is rather more complicated. The solvent just solve more or less silver depending on its amount and time of being applied.

    First you have to solve or state the answer what do you need the reversal for. Scan, projections or copying purposes? Than you can decide the right amount of solvent. I use the process for making slides for projection and my aim is to have enough halide solvent to have clear highlights but not to much so I have deep blacks in shadow areas... most of the conventional films are of rather less contrast I think, but I didn't make enough experiments with enough films.

    Anyway, good luck and keep posting your results.
     
  18. alxsav

    alxsav Member

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    Success! Well kind of... Finally I got some usable positive image on the Rollei Retro 100. I skipped solvent in FD, reduced the permanganate and bleaching time, skipped Clean and fix and increased the second exposure a lot. I don't know exactly yet as the film is still wet and I need to get some sleep. It looks somewhat dark though. Tomorrow I will report and post some scans hopefully!
     
  19. brucemuir

    brucemuir Member

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    I use Stannous Chloride to do a chemical re exposure instead of second exposure to a light bulb.

    This makes the re exposure step much easier.
     
  20. Existing Light

    Existing Light Member

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    Glad you're finally getting something useable. Probably not a good idea to skip the clear bath (if that's what you mean when you say "skipped Clean." The fix step, according to Ilford, is optional, but should probably be done.

    If they're dark, the film is underexposed or underdeveloped. you'll have to adjust one or both of those variables.

    Looking forward to seeing some scans. Good luck. Your next roll should look better than this one :smile:
     
  21. Steve Roberts

    Steve Roberts Member

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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
     
  22. John Austin

    John Austin Member

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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
     
  23. bluesun267

    bluesun267 Subscriber

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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.
     
  24. bluesun267

    bluesun267 Subscriber

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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 a moderator: Mar 26, 2012
  25. alxsav

    alxsav Member

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    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?