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  1. #1
    NDP_2010's Avatar
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    Black and white slides / reversal process diagnose problems?

    Hi,
    Try out reversal process for the first time I am using Ilfords information that can be found on google www.ilfordphoto.com/Webfiles/20061291034093.pdf

    basically, 10g /L thiosulfate in first dev; 1% sulfuric acid + 2g/L potassium permangenate bleach; 25g/L metabisulfite clearing, expose, develop, fix

    I first had problems with the slide being too dark, ie highlights were very dense. I exposed the film for about 1min close to 2 fluro tubes. Im not sure if this was exessive exposure as I also repeated the process again further away and for 45 seconds and it also gave dark results. Should I use a weaker light source or is this a problem with not developing the film initially for long enough? (I developed the film for 8 minutes= I am using HP5+ which is close to normal development time for negative)
    Ilford reccomends 12 minutes for panF so I am unsure if i should dev hp5 for longer.

    On my second attempt all seemed fine untill 2nd dev, when i poured it out it was tinted with grey. I later found out that this was most likely the silver halide as my slide was completely clear. What can cause this? Is it possible I did not wash out the clearing solution for long enough and it some how cleared off the emulsion during development?

    Also, how long is it possible to keep first and second developer- how many rolls can be expected from these? Similar to normal negative development or a shorter lifetime?

    Many thanks for your help

    --------------
    summary of questions

    -is using two fluro tubes (similar to ceiling lighting) too strong for second exposure?
    -what can cause the emulsion to come off during second development? (contamination from clearing solution?)
    -what is the lifetime of the bleach, clearing solution and developers in reversal processing?

    pentax 6x7,canon eos 300, crown graphic 4x5

  2. #2

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    Quote Originally Posted by NDP_2010 View Post
    Hi,
    Try out reversal process for the first time I am using Ilfords information that can be found on google www.ilfordphoto.com/Webfiles/20061291034093.pdf

    basically, 10g /L thiosulfate in first dev; 1% sulfuric acid + 2g/L potassium permangenate bleach; 25g/L metabisulfite clearing, expose, develop, fix

    I first had problems with the slide being too dark, ie highlights were very dense. I exposed the film for about 1min close to 2 fluro tubes. Im not sure if this was exessive exposure as I also repeated the process again further away and for 45 seconds and it also gave dark results. Should I use a weaker light source or is this a problem with not developing the film initially for long enough? (I developed the film for 8 minutes= I am using HP5+ which is close to normal development time for negative)
    Ilford reccomends 12 minutes for panF so I am unsure if i should dev hp5 for longer.

    On my second attempt all seemed fine untill 2nd dev, when i poured it out it was tinted with grey. I later found out that this was most likely the silver halide as my slide was completely clear. What can cause this? Is it possible I did not wash out the clearing solution for long enough and it some how cleared off the emulsion during development?

    Also, how long is it possible to keep first and second developer- how many rolls can be expected from these? Similar to normal negative development or a shorter lifetime?

    Many thanks for your help

    --------------
    summary of questions

    -is using two fluro tubes (similar to ceiling lighting) too strong for second exposure?
    -what can cause the emulsion to come off during second development? (contamination from clearing solution?)
    -what is the lifetime of the bleach, clearing solution and developers in reversal processing?

    I've used Ilford's method in the past with good results, with the slower films. Not sure about the developing times for HP5+, but I would have thought that a similar time to Pan F would be a good starting point.

    As Ilford say, 2-4 times the basic second exposure should not cause problems (better more than too little time), but excessive exposure or sunlight can cause problems.

    I recall once that the bleach stripped the emulsion completely!
    (Sulphuric acid and permanganate is quite strong stuff) I can't recall the type of film, might have been an older film with a softer emulsion, but IIRC I think that I might have given the film too long in the bleach (just to be on the safe side? ). Best to stick to the recommended times.

    Not sure about keeping times of the solutions..with all processing I tend to discard the working solutions after the session, even if it means storing up sufficient films to use up the chemicals economically.

    Hope you sort out any problems...projected B & W slides look amazing if well done.

  3. #3

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    The potassium permanganate bleach makes the emulsion extremely soft and fragile. I have seen the emulsion essentially melt away in the second developer as well. A couple of suggestions: Use Kodak D-19 with the thiosulfate for your first developer and unaltered D-19 for the second developer. Keep temps near 68F. Do not let the developer get too hot. Also, you may want to cut back slightly in the amount of potassium permanganate used to make the Solution A bleach. If reversing an old-school emulsion like Efke/Adox the permaganate should be roughly cut in half (from 2g to 1g per 500 ml water). Do not alter the strength of Solution B. Do not worry about "over exposure" prior to second development. Bring it out in the light and thoroughly expose the emulsion taking care not to scratch it. Always use a hardening fixer after second development.

  4. #4

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    If I recall correctly, gelatin melts because there's a huge shift in pH between the first developer and the bleach. It's not because of the permanganate. It does nothing to harden the emulsion, contrary to what dichromate does. So keeping that shift to a minimum will solve your problem of gelatin melting.
    Also using a temperature of 18°C helps.
    Try using the first developer with a diluition factor like 1+3 or 1+4 and lengthen the developing time accordingly . This will slightly lower the pH. Then try to cut the permanganate in half. The idea is to find the bare minimum of each and every chemical specimen that will work one-shot and will avoid ruining the emulsion.
    Try also to add some glutaraldehyde (such as Rollei Rbm5) in a bath between the first developer and the bleach, sort like of an hardening stop bath.

  5. #5
    NDP_2010's Avatar
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    Thankyou for the quick and detailed replies.

    Do you think lc29 is a suitable developer for this process or possibly rodinal?

    Any other advice would be much appreciated. I am currently purchasing some dichromate and possibly try out some slower films.
    pentax 6x7,canon eos 300, crown graphic 4x5

  6. #6

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    Quote Originally Posted by NDP_2010 View Post
    Thankyou for the quick and detailed replies.

    Do you think lc29 is a suitable developer for this process or possibly rodinal?

    Any other advice would be much appreciated. I am currently purchasing some dichromate and possibly try out some slower films.
    I would only use high-contrast developer such as paper developer. Also Kodak D-19 is excellent. I've had very good results using Tetenal Eukobrom for instance. I think any paper developer can do.
    Negative developers are not convenient in that you have to tweak them in order to obtain a decent contrast.
    You sure can do it, for instance adding some sodium carbonate or some sodium hydroxide.
    With paper developer you eliminate one possible variable (hopefully choose and use the same developer in your tests).

  7. #7
    Athiril's Avatar
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    I gave up on permanganate, and use a dichromate bleach, never looked back. Reliable bleaching every time.

  8. #8
    Oxleyroad's Avatar
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    I concur with both Alessandro on the developers as I have successfully used both, and Athiril on the dichromate bleach. I too have never looked back since moving away from permanganate bleach.
    Cheers - Andy C
    ---------------------

    16mm Cine, 35mm, 120, 5x4 & 7x5.

  9. #9
    NDP_2010's Avatar
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    Thanks oxley,

    if using high contrast developer (possibly multigrade paper devloper has been suggested by some), how long would I do first and second developments on film such as fp4 or hp5?
    pentax 6x7,canon eos 300, crown graphic 4x5

  10. #10
    Oxleyroad's Avatar
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    I have not run any Ilford film to date as reversal, don't have much of it. I have run Foma negative and reversal, Shanghai GP3, Orwo UN54, Silvermax and Kodak Tri-X reversal as well as Kodak colour Vision2 cine neg film. The Silvermax and colour negative film needs longer developing times than the other films, so I do not dilute the developer and run for the same times as below.

    I shoot all my film at box speed, but the colour neg at 1 stop under.


    I cannot give a time for multi grade developer, but my times for D19 dilute stock 1:1 at 23degC which I am using right now with Foma R100 both 35mm and 16mm.

    Dev 1- 3min 30 const agitation
    wash
    bleach - 60 sec const agitation
    wash
    clearing bath - 60sec const agitation
    wash and open tank to dark room lighting 2x 75W globes for 2 to 5 mins
    Dev 2- 90 to 120 sec. Same developer as Dev 1
    Wash
    Fixer - 2 mins
    wash

    I have run many test strips of bracketed film, and I do this for each new developer or when I store mixed developer for more than a fortnight just to confirm my times.

    Trust this helps.
    Last edited by Oxleyroad; 12-19-2012 at 05:04 AM. Click to view previous post history. Reason: Added box speed
    Cheers - Andy C
    ---------------------

    16mm Cine, 35mm, 120, 5x4 & 7x5.

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