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  1. #1

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    Ansco 130 restrainer question (PE, G. Koch please chime in also)

    Ansco 130 contains 5.5g/l potassium bromide. This seems high, but my understanding is the higher amount is there to make the formula slightly warmer, not just prevent fog. I'd like a cooler version of 130 - to use with MGWT. One of the more simple ways suggested by Anchell is to replace some or all of the bromide with benzotriazole. One example is Wimberley's version of 130, which uses 0.2g/l benzotriazole in place of the bromide. But I am confused by a few things:

    1. The "Cookbook" suggests 0.2g benzotriazole has the same anti-fog effect as 1g bromide restrainer. If that is true, Wimberley's formula implies regular Ansco 130 should only need 1g/l potassium bromide to prevent fog. Is this right? Could the amount of bromide in 130 simply be reduced from 5.5g to 1g? It seems to me this would make the formula slightly less warm, without using benzotriazole.

    2. The "Cookbook" suggests even the 0.2g/l benzotriazole in Wimberley's 130 is higher than necessary to prevent fog. How much is required? Or, how much bromide restrainer is really required in the original 130 to prevent fog?

    3. Is reducing the bromide and/or replacing it with benzotriazole even going to make a meaningful difference with current chlorobromide VC papers? The "Cookbook" gives the impression this "cooling" effect is most effective with bromide papers. So maybe this is a waste of effort.

    Michael

  2. #2
    eclarke's Avatar
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    Here's my variation which has a few followers. I've used thus for eight or nine years now...especially nice with Ilford WT FB.


    Cooltone 130 paper developer**makes 1L stock

    750 cc water @125 deg.
    2.2 grams Metol
    50 grams Sodium Sulfite
    11 grams Hydroquinone
    80 grams Sodium Carbonate (anhydrous)
    11 grams Glycin
    15 cc 1% Benzotriazole solution
    Water to make 1L.


    Mix in order shown. Add a pinch of Sodium Sulfite to the water before adding Metol.

    I dilute 1+3…..

    I like to run the tray at 73 degrees

    80 g. anhydrous carbonate is important.

  3. #3

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    Thanks eclarke, if I'm reading this correctly it is Wimberley's but with .15g benzotriazole instead if .2g. A couple of questions:

    1. Can sodium carbonate monohydrate be used in place of anhydrous if the amount is adjusted accordingly?

    2. How do you mix your benzotriazole solution?

    3. Why do use this at 1:3 vs the standard 1:1 dilution for regular 130?

    4. What is your normal development time with MGWT FB?

    Thanks.

  4. #4
    eclarke's Avatar
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    1. Anhydrous is more stable but if you adjust it it's fine..don't cut it short
    2. I have good stirring equipment (Corning heated magnetic stirrers)
    3. Because it works
    4. It depends on the exposure in the enlarger, but I shoot for 2 minutes but am prepared to snarch it early if necessary.

  5. #5

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    Quote Originally Posted by Michael R 1974 View Post
    .................2. How do you mix your benzotriazole solution?..........
    It will dissolve in water better if it's a bit alkaline. Since you're making a developer with quite a lot of carbonate, a pinch of that could go into the water in which you're making the benzotriazole solution. You won't have to account for the carbonate in it when formulating the developer, since it is insignificant.

  6. #6

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    Thanks guys.

  7. #7

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    Benzotriazole is usually used as a 1% solution and potassium bromide as a 10% solution. Usually the same amount of solution is used whether BZT or KBr. I don't know where Anchell gets his figure of 0.2 g of BZT. In general I am rather skeptical of Anchel's book. I would suggest making up Ansco 130 without either chemical and then adding small amounts of each until you obtain the image tone you are seeking. I have done this myself with another paper developer to get a purely neutral black which I favor.

    A 1% solution of BZT is easy to make without resorting to any other chemicals. But you need to start with hot water or else do a lot of shaking.

    The amount of resttainer is dependent on the paper used. What is listed in formulas is a compromise vaule which may not be ideal for the paper you are using.
    Last edited by Gerald C Koch; 07-01-2012 at 06:34 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  8. #8

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    Hi Gerald, Anchell seems to refer to the use of a 1% benzotriazole solution when modifying PQ developers for colder tones. He refers to the use of a 2% benzotriazole solution (and the ratio I quoted) for modifying MQ developers for colder tones. Of course, he warns there are no hard and fast rules, and that testing is required.

    Perhaps I will also try to contact John Wimberley's regarding W130B which, as I described above, is identical to 130 except that the 5.5g/l of bromide restrainer is entirely replaced with .2g/l benzotriazole.

    The large amount of bromide in regular 130 is interesting. Among other things it would help explain why 130 is reputed to work so consistently from print to print.

  9. #9
    RalphLambrecht's Avatar
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    Quote Originally Posted by eclarke View Post
    , but I shoot for 2 minutes but am prepared to snarch it early if necessary.
    not a good practice. Pulling the print prematurely makes for low-contrst midtones and weak shadows.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  10. #10
    Shawn Dougherty's Avatar
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    Quote Originally Posted by Michael R 1974 View Post
    130 is reputed to work so consistently from print to print.
    This has certainly been my experience.

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