measurement tool for pt/pd

Discussion in 'Alternative Processes' started by pateeid, May 15, 2009.

  1. pateeid

    pateeid Member

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    i have problem with the large print.i guess because i still use dropper. HAve anyone have problem with dropper? any idea how to measure the chemical for consistence print?
     
  2. PVia

    PVia Member

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    Currently I use a 2ml dropper for my 9x13.5 images.

    I believe I use approx 3ml of #1/Pd solution total. I just measure 1.5ml of each chemical (separate droppers) according to the marking on the dropper, instead of counting drops.

    Works perfectly for me...
     
  3. Vaughn

    Vaughn Subscriber

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    I have noticed that the size of the drops do not seem to be very consistant between droppers. But about 15 drops equals a ml, I believe. So if you can accurately measure out ml's, or even better .5ml, then do away with the droppers.

    How many drops do you need per print? Use water and put that many drops in a measuring cylinder. If there is not enough solution to accurately measure out by the ml, you might be able to mix up enough for two or three prints at a time, then after mixing, divide it up.

    Vaughn
     
  4. Lukas Werth

    Lukas Werth Member

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    Depending on the size of the print you might find it convenient to switch to cc. 20 drops normally make up one cc. When measuring, just use a beaker with an exact cale, and watch the surface of the fluid exactly (it will be somewhat concave, and it is worthhile to take this into account. Also, I would use a few drops of water to "clean" the beaker afterwards, and get out any precious metal left back in it. This will somewhat dilute the sensitizer, but that won't matter.
     
  5. sly

    sly Subscriber

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    I have a number of syringes. The small 1ml ones (used by diabetics) measure increments of 0.1ml. I also have 3ml, 5ml, 10ml and 12 ml. I don't just use them for alt printing, but for measuring concentrates of stop, photoflo, rodinal, etc. I label each with permanent marker, to prevent cross-contamination.
     
  6. Softie

    Softie Member

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    If you're familiar with pipettes, I'd go with them. They're repeatable, washable, and can be purchased in a dizzying variety of capacities. I keep some 10 mL pipettes on hand for darkroom work.

    You can also weigh your solutions. Tare off the final container and then measure your ordinary quantities. As long as you don't change your solution concentrations, everything should work fine.
     
  7. scootermm

    scootermm Subscriber

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    Use Pipette and pipette pumps.
    I use 5ml versions.
     
  8. deisenlord

    deisenlord Member

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    Note they make plastic pipette's as well as glass ones if your worried about breaking the glass ones.
     
  9. Dana Sullivan

    Dana Sullivan Advertiser Advertiser

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    If you are using standard eye droppers, use only plastic ones. The glass kind have far too much variation in them to be repeatable for photographic use. Plastic droppers are medical grade and the openings are cut and sized at the factory for consistent drop size.

    For the most consistency, I always lift the dropper straight out of the amber bottle, then over my shot glass. I never turn the dropper horizontally as I count drops, as I've often seem, because I find that the drops will cling to the side of the dropper, sometimes giving very small drops, and other times very large.

    As others have mentioned, glass pipettes are extremely accurate and are kinda cool, as well.
     
  10. pateeid

    pateeid Member

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    I use 36 drops of 1 for my 7x17. It's good to know that 15 drops equal 1 ml
     
  11. Jeremy

    Jeremy Member

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    Well, all you know is that the droppers that person owns has 15 drops = 1 mL. I would suggest a little test that costs nothing except time (and a graduated cylinder if you don't have one): get a cup full of water and a graduated cylinder. Count out the drops it takes to get 5mL as measured by the graduated cylinder. Do this 5 times. Add the number of drops from each together and divide by 25 and you'll have a good average of # drops/mL for that dropper.
     
  12. Vaughn

    Vaughn Subscriber

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    Definitely worth checking out the volume of your 36 drops, but it probably will be somewhere around 2 ml. It would be good to find a graduated cylinder that can measure to the closest 0.1ml...or at least .25 ml...if only to keep you from having to count out 72 drops for every print!

    I have medical syringes (w/o the needles!) that measure to 0.1 ml -- up to 3ml. Something like that would be nice to use to draw out the solutions...pouring out small volumes is not easy and asking for accidental spills. Not a big deal with Sol #1 or #2, but costly with platinum or palladium! I use the syringes to shoot the mix under the edge of my puddle pusher.

    Vaughn
     
  13. pateeid

    pateeid Member

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    where can i order some good pipette and pipette pump from? i still looking and it has so many variety of measurement scale such as ul