Help with photo flow dilution for 650mL?

Discussion in 'B&W: Film, Paper, Chemistry' started by bessa_L_R3a, Mar 19, 2008.

  1. bessa_L_R3a

    bessa_L_R3a Member

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    Hi,

    1) I have a bottle of Photo Flo concentrate. It says the working solution is made from 1 part concentrate to 200 parts water. A friendly Apug' er told me he mixes 5mL of concentrate with 1000 mL but I'm really only interested in making enough for two rolls at a time in a 650mL tank.

    Would really appreciate some help figuring out the proportions.

    2) On a related note, I notice that on my dried negatives, there are streaks. Is this the Photo Flo residue that didn't quite drip off completely? To get rid of them, I use Rexton Anti static film cleaner with PEC pad non abrasive wipes.

    But what's the solution to avoiding these streaks?

    Thanks,

    Robert.
     
  2. dances_w_clouds

    dances_w_clouds Subscriber

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    Your mixing it 2 strong. 1 teasoon full in a litre of water should be plenty.
     
  3. Anscojohn

    Anscojohn Subscriber

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    About 3ml of Photo-flo would be about right. And try using distilled water. That should eliminate drying marks.

    John, Mount Vernon, Virginia, USA
     
  4. Phillip P. Dimor

    Phillip P. Dimor Member

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    This isn't the most scientific way to do it.. I never mix a working solution as it does not keep (it will grow mold and get scummy if you keep it).
    If you're only doing two rolls at a time, I fill my developing tank with water and stick my finger into the photoflo bottle. I remove my finger and let 1-3 drops of photoflo drop into the developing tank with water. I then stick my reels with film into the tank and gently spin them or agitate lightly to mix the photoflo. Works for me. The residue could be deposits from your water. Where I live the water quality is all over the place. I've also gotten streaks with photoflo that has been mixed too strong.

    When you add the drops, notice the surface of the water and how the photo flow spreads. Once it starts looking like soap water, if it starts forming bubbles or looking like you could wash dishes with it, you've mixed it too strong. You want to just break the surface tension of the water.

    Hope this helps. If anyone does it a better way, or if i've been doing it wrong for the past few years, please let me know.
     
  5. dances_w_clouds

    dances_w_clouds Subscriber

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    Yes water quality is important I use really soft water which works well with VERY little Photo Flow A teaspoon would actually be TOO much Thats why the streaks.
     
  6. bessa_L_R3a

    bessa_L_R3a Member

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    Yes, I did notice that there was a lot of froth .... ha ha ... ok, I will try Dimor's method of adding a few drops. I guess it doesn't have to be an exact science ...

    Gracias.
     
  7. MattKing

    MattKing Subscriber

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    We have soft water here. One drop is enough.

    Matt
     
  8. ic-racer

    ic-racer Member

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    The correct amount of photoflo for 650 ml would be 3.25ml. This can be easily measured with a pipette or a 5ml syringe.