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  1. #11
    Lopaka's Avatar
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    Thanks for all the replies - now I have some ideas to play with when I have the time. Will try to let you know results in a week or two.

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  2. #12

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    Quote Originally Posted by Lopaka View Post
    Thanks for all the replies - now I have some ideas to play with when I have the time. Will try to let you know results in a week or two.

    Bob

    Please do. Have you tried anything yet?


    Wayne

  3. #13
    Lopaka's Avatar
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    Quote Originally Posted by Wayne View Post
    Please do. Have you tried anything yet?


    Wayne
    Sorry I haven't been back to this thread - Iv'e been busy preparing work for an exhibition. I did order some chemistry this morning, with luck I will be able to run some controlled testing by the end of next week.

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  4. #14
    Lopaka's Avatar
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    Preliminary test results

    Preliminary testing results on substituting other B&W developers in Ilfochrome:

    First, I asked another photographer who at one time was a tech rep for Ilford USA and his job was to travel around and teach pro photogs how to use Ciba/Ilfochrome. When digesting his reply, note the source: " Yes, dev and fix are variants of B&W chemistry and I've found other developers to be inferior, and further, if you do not use Ilfochrome fixer, you will not get archival results." OK, so much for the company line.

    Testing conditions as follows:
    Printing from a known image, one 8x10 each developer variant, same enlarger height, f-stop, time and filter pack. All from the same box of paper. All processing done on JOBO CPP-2 once and dump. Bleach and fix drawn from same working solutions mixed for the session. Alternate developers run at same time/temp as Ilfochrome dev. Where there is ref to sodium thiosulfate, it is crystal obtained from Digitaltruth, what looked to be approx 1/4 teaspoon weighed out at 0.8 gram on lab scale accurate to +/- 0.1 gram. Where used, it is at 0.8g/litre of working solution dev. Control print made with fresh Ilfochrome developer in same session.

    1) Dektol 1:3 - print ok density/contrast with some yellow shift, looks to be correctable with filter change

    2) Dektol 1:3 w/sodium thiosulfate - same as (1) but a bit lighter, like somewhat overexposed

    3) Ilford Warmtone 1:9 - almost a match for (1)

    4) Ilford Warmtone 1:9 w/sodium thiosulfate - pretty good match for (2)

    Note that this is not a comprehensive test as only one image was printed and cannot identify whether differences in highlight/shadow detail can be acheived with different types of images.

    Anyway, this is a start - as always YMMV.

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  5. #15

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    Quote Originally Posted by Lopaka View Post

    1) Dektol 1:3 - print ok density/contrast with some yellow shift,
    Thats exactly what the hypo is in there for. My limited understanding is that there is an excess of yellow dye in Ilfochrome to ensure that there is enough in the shadow areas, and the hypo removes the excess where it isnt needed. Or something like that. But you're going to need it in there.

    Thanks for posting your results!

    Wayne

  6. #16
    davetravis's Avatar
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    Thanks Bob for not only taking the time to do this experiment, but also for posting the results here on Apug.
    I'll be printing some BW soon, and time permitting, will try some of this also.
    D.

  7. #17
    Lopaka's Avatar
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    Note that I have not yet attempted to make corrected prints - that will be round 2. Close examination of round 1 reveals that Ilford Warmtone w/sodium thiosulfate is closest to the control, although in theory at least, none is so far off that they could not be corrected to match, We'll see.

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  8. #18

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    I came across one of the old divided developer formulas that used to work, back in the day (ie before my day). They only contain 1/8 teaspoon of hypo/liter. I tried quite a few using that quantity. I never had any troubles using that amount of hypo (they just didnt do much for contrast), so you might want to try that. Or you can derive your own optimal quantity from testing. Have fun.


    Wayne

  9. #19
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    Apologies for taking so long to get back to this thread. Here is what seems to be the simplest answer:

    When developer part B turns dark and no longer works, substitute Ilford Warmtone B&W developer in the mix. Use the same amount of Warmtone as you would have of part B and continue to use parts A and C as indicated. It's part B that contains the developing agents that die an early death after the bottle has been opened. Warmtone is not precisely the same formulation, but close enough that when used with the existing parts A and C produces results that require very little adjustment.

    At least that seems to be a workable answer when you are absent from the Ciba process for a few months.

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  10. #20

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    Quote Originally Posted by Lopaka View Post
    Apologies for taking so long to get back to this thread. Here is what seems to be the simplest answer:

    When developer part B turns dark and no longer works, substitute Ilford Warmtone B&W developer in the mix. Use the same amount of Warmtone as you would have of part B and continue to use parts A and C as indicated. It's part B that contains the developing agents that die an early death after the bottle has been opened. Warmtone is not precisely the same formulation, but close enough that when used with the existing parts A and C produces results that require very little adjustment.

    At least that seems to be a workable answer when you are absent from the Ciba process for a few months.

    Bob
    Bob,

    Does your discussion and apparent usage of an alternative developer imply not all ILFOCHROME process solutions are used at the same rate, or simply that one component has a short shelf life?

    Tom

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