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Thread: A real formula

  1. #61

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    Hi, I just tried this formula in a smaller scale (20x less) and I added almot 8ml of Ammonia (22%), wich gives me a brownish/dark solution is that usual or is there something wrong with the ammonia I m using ?
    It became clearer, but not clear, so I decide to stop adding ammonia.
    Once the solution had been added to salted A solution, the precipitate was white as usual.

    Now it's in the oven a 50°C in a water-thing (bain-marie), for the next 30 minutes.

    Hopes this will work , it's my first type adding ammonia and using your formula, usually, everything worked fine but was verrrrrry slow (1/4 iso at best) .

  2. #62

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    The silver solution does turn brownish when you start adding the NH4OH solution. It should be pretty clear when you get more in.

    Good luck, I'm sure you'll get more speed than ISO 1/4!
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

  3. #63

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    Ok thanks ! now it's chilling waiting tomorow morning until wash, re-melt and adding gelatin to reach 7%

    good day or good night

  4. #64

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    as somebody noticed it before, after one night in the fridge , the emulsion is still liquid, maybe our gelatin are different ? To make washing possible I heated the solution at 35°C, added the weight of gelatin to make it 7% of the final solution, hope that would fix the problem

  5. #65
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    The gelatin should set up overnight unless it falls below about 2% or if you heat it too hot for too long.

    PE

  6. #66

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    If Google is God, is Yahoo The Devil ?

    Quote Originally Posted by Photo Engineer View Post
    The gelatin should set up overnight unless it falls below about 2% or if you heat it too hot for too long.

    PE
    OK,
    At the risk of sounding stupid again-The formula,as written, has gelatin at under 2% from the gitgo. I have wondered if all that water is needed.
    Bill

  7. #67
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    Guys;

    Please look at this thread from post #50 onward. In those posts we discuss this problem in detail. At some point in the make, you adjust the gelatin to 5% - 10% by adding solid gelatin or by adding 20% gelatin solution if that is usable.

    Bill, if you look at the formula in your notes, as we discussed before, you will see exactly how this is done.

    If the emulsion is too thin to set up, add the gelatin before the wash, if it sets up add the gelatin after the wash. You are all missing that crucial line. Now, the reason for the order of adding the gelatin is this. If you noodle wash and make it 10%, it can become too hard to run through the noodler, so you can add some gelatin before and some after the wash.

    You have all apparently forgotten the early parts of this thread, the details of the OP and the exact instructions in the workshop notes.

    Sorry.

    PE

  8. #68

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    PE - in post #52, you write, "Please note in the OP that I suggest adjusting the gelatin to 5 - 10%. This can be done before or after the wash."

    In the original post, adding gelatin is listed as the step after the wash. It looks like before the wash would work better for most people.
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

  9. #69
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    Kirk;

    You are right and it depends on the gelatin and how well it sets up. Personally, I have found it works best before the chill set. I add as you said earlier, at the start of the heat set. I use dry gel to avoid further dilution. I also gave the amount of gelatin that I added.

    The strategy is this: Low gelatin promotes formation of large grains for speed. Adding gelatin protects during further heating and I have found that it helps to be there during digestion.

    PE

  10. #70

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    Hello PE,
    My fears have been realized! My last post dose make me look stupid. But your last post finaly passed through my skull and I do understand that a lower viscosity promotes grain growth.
    Humbly,
    Bill



 

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