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  1. #1
    Maine-iac's Avatar
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    Divided Developers for B&W paper

    Several people have inquired about the divided developer printing method I use.

    First, some general remarks: Divided developing is not a new idea. I ran across it first about 25 years ago in an old Dignan booklet of formulas, and have used it ever since. The concept is simple: by separating the activating agent from the developing agents into two separate baths, several things are accomplished:

    1. Time/temperature considerations virtually disappear. Since no image appears in the developing agent bath (Bath A), any temperature will do. I've tested at temps ranging from 50F to 100F with no discernible difference. I've even had Bath A at room temp and Bath B 50 degrees warmer and everything was fine. Just came up faster in Bath B. Your ambient darkroom temperature will do just fine. All that happens in Bath A is that the latent image created by exposure under the enlarger absorbs the amount of developer it will need to fully convert the silver ions. As a result, Bath A never becomes exhausted; it only get used up physically in volume as each sheet of paper absorbs a tiny amount. It can be re-used indefinitely. Generally, about 20-30 sec. in Bath A is sufficient for the absorption to take place.

    2. Since no actual image appears in Bath A, and in Bath B, only the absorbed developer is activated, one cannot over- or under-develop as long as sufficient time is given for absorption of the solution. Any density changes will have to occur under the enlarger, thus making you become a better printer.

    3. Contrast is automatically controlled. You cannot increase or decrease contrast by leaving it in the soup longer or pulling it out sooner. You can leave it in Bath B all day and it will develop no further than what the absorbed developer from Bath A permits. Again, learn to control contrast under the enlarger. EXCEPTION: by using a soft contrast developer formula for Bath A instead of the harder formula, you can decrease contrast approx. 1 paper grade.

    4. 2 liters of Bath B, which is just sodium carbonate (Arm & Hammer Washing soda) will process approximately 35-40 8 X 10's before beginning to become exhausted (weak blacks, muddy grays). Just discard and replace, at a cost of mere pennies. While the image can't over-develop, it can under-develop if you pull it too soon. At a normal ambient temp of around 70 degrees, it usually takes about 45 seconds to fully develop. The warmer your developer or room temperature, the shorter time it will take. I've never had it take longer than 45 seconds, even with a weakened solution. So the total time saving per print is considerable.

    5. Bath A will keep more or less indefinitely, because the preservative is in it, but not the activator. Don't contaminate Bath A with Bath B or you turn it into a weak single-solution developer and all bets are off. In actual fact, I've kept it going for as long as 9 months without noticing any degradation. Once I had to stop printing for nearly a year, and the solution did go bad during that period. So figure on a 6-9 month shelf life before mixing fresh (again, at very low cost).

    This method also works well with Ilfochromes (eliminates the temp control problems and naturally controls contrast) though with a different Bath A formula. Another topic for another day.

    Caveat: I am not a chemist (Ph.D. in biblical studies and early Christian origins--- an almost totally useless field of knowledge---which along with $3 will buy me a cup of coffee almost anywhere), and my quantities, arrived at through experimentation, work, but are not necessarily the optimum in terms of interactions and proportionality. I'm sure Pat Gainer or others with more knowledge of chemistry can tweak them to be more correct. Here are the formulas I've been using for years quite successfully:

    Normal-hard Bath A to make 2 liters

    2 teaspoons Metol
    3 Tablespoons Sodium Sulfite
    2 teaspoons Hydroquinone
    1/4 teaspoon Potassium Bromide
    OR
    10 ml Benzotriazole (not both)


    Soft Bath A

    2 Tablespoons Metol
    3 Tablespoons Sodium Sulfite
    1/4 teaspoon Potassium Bromide
    OR
    10 ml Benzotriazole (not both)

    Bath B

    2 liters water
    1/2 cup sodium carbonate

    No water rinse or stop bath between Bath A and Bath B.

    I've also tried E-72 which is a Phenidone, Vitamin C formula for Bath A, but find that with the divided development technique, an extra boost is needed, so I add a teaspoon or two of Hydroquinone to the Phenidone, Vitamin C for Bath A, and that does the trick.

    Larry Kalajainen

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    Interesting. Do you tray develop Ilfochrome? I know, you said it was a subject for another thread.

  3. #3
    Maine-iac's Avatar
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    Quote Originally Posted by psvensson
    Interesting. Do you tray develop Ilfochrome? I know, you said it was a subject for another thread.
    Yes, I began using a drum, but later switched to trays when I figured out that divided developer was a great way to control contrast with Ilfos. Also after some years, my drum's cap began having problems with light leaks. Since temp is not a consideration, trays just seemed easier. And since as soon as you put it in the bleach, you can turn the lights on, it meant that only the development step needed to be done in the dark. Just more convenient, for me anyway. The bleach step takes a bit longer at cooler ambient room temps.

    Before I write a thread about it, I'll have to find out if things still work the way they used to. Ilford has made some changes in their emulsions--they now make several contrast grades-- and I'm not sure my formula will work as well with them. I haven't done any Ilfos for several years.

    Larry

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    Bob Carnie's Avatar
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    Larry

    When you did ilfocromes or cibas in the past were you mixing your own chemicals for the process or buying them commercially??????

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    Quote Originally Posted by Maine-iac

    Before I write a thread about it, I'll have to find out if things still work the way they used to. Ilford has made some changes in their emulsions--they now make several contrast grades-- and I'm not sure my formula will work as well with them. I haven't done any Ilfos for several years.

    Larry
    I'd appreciate that. I've considered Ilfochrome, but the drum processing has been putting me off.

  6. #6
    Ole
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    Interesting, this... I've used two-bath developer for film, but never thought of doing it with paper!

    Could you post this in the "Chemistry Recipes" section, please?
    -- Ole Tjugen, Luddite Elitist
    Norway

  7. #7

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    I used the Dignan technique with Cibachrome years ago - and it worked fairly well.

    IMO, used by itself for Cibachrome contrast control, it worked nowhere near as well as unsharp masking. It is basically a Beers developer concept that Pat converted to a two-bath.
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  8. #8
    Maine-iac's Avatar
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    I'll be glad to post it in the Chemistry Recipes, Ole.

    Larry

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    Maine-iac's Avatar
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    Replying to both Bob and Tom:

    I mixed only my own developer, although I sometimes used regular Ilford Rapid Fix if I ran out of the fixer in the Ilfochrome kit. Always seemed to work exactly the same.

    The divided development technique is not exactly like the Beers technique. Beers is a two-bath system with each bath being a complete developer--developing agents and activator--one "hard" and one "soft." True divided development separates activator from developing agents.

    While it's true that many developer formulas, separated, would not give as great a contrast control for Ilfos as unsharp masking, I'm not sure that holds true for the formula I was using, which was essentially a slightly modified one that appeared in an article in Photo Techniques about 10 or more years ago. Strikes me in the dim recesses of my memory that the author's name might have been Springer, but I won't swear to that. Before that, I had already been experimenting with various divided formulas for probably 10 years, finding out which ones controlled contrast and which didn't. It was not long after I began using divided development for all of my B&W printing that it dawned on me that it would probably work for Ilfochrome, too. By the time I read Springer's (?) article, I had already worked out that Phenidone was better than Metol because Metol caused a decided shift toward yellow that had to be compensated for by heavier filtration, thus making even longer exposures. With Phenidone-based formulas, I usually needed very little filtration at all.

    Anyway, the formula was inherently lower contrast in that it contained no HQ and did contain a wee bit of sodium thiosulfate. Apparently, Ilford used a bit of hypo in their own developer. Some photographer friends, on seeing my Ilfos, would be convinced that they were really "C" prints because the highlight detail held so well. So I never bothered to learn unsharp masking, so I really can't refute what you say, but can say that I never felt the need for it.

    Larry

  10. #10
    Bob Carnie's Avatar
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    Thanks Larry

    My problem is with the bleach for ciba, I would possibly give my right baby toe to learn this formula, I would also possibly give up my left toe if anyone could give me the formula for Champion Nova Lith A B.
    After that I would consider more appendages for formulas, dependent upon how my balance is missing 2 digits.

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