Looking for a Thermometer

Discussion in 'Darkroom Equipment' started by Existing Light, Oct 22, 2009.

  1. Existing Light

    Existing Light Member

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    I'm currently using a digital thermometer from Target to measure the temp of my chems, but I tend to drop it in the water a lot, so I know know it's likely to die eventually. I'm looking on Freestyle for a thermometer, and I've narrowed it down to two.

    The first one is the Legacy Pro thermometer, which is 3.99USD http://www.freestylephoto.biz/62010-LegacyPro-6-inch-Glass-Thermometer

    The other is the Patterson, which is $25.99. http://www.freestylephoto.biz/62010-LegacyPro-6-inch-Glass-Thermometer

    Of the two, which is more accurate, or are they the same accuracy wise? If they are, the LEgacy PRo will be the one I get. The Patterson has the metal tip, which seems to me like it would adjust to changing temps faster since the liquid in the thermometer (Alcohol, I'm assuming) is in contact with the tip (or appears to me to be). The Legacy Pro looks from the picture like the thermometer is encased in a glass tube. Would that have any effect on accuracy? If it's not in direct contact with the water, wouldnt the reading be slightly off if the water temp is changing because the temperature of the air has to drop before there's a change in the reading of the thermometer?

    Am I just overanalyzing a trivial matter?
     
  2. fotch

    fotch Member

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    The link is the same rather than two separate links. :smile:
     
  3. AgX

    AgX Member

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    About dropping the thing in the bath:
    Long ago there was a thermomether (Agfa?) that was designed to float upright in the bath.
     
  4. dancqu

    dancqu Member

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    An Enormous Selection!

    Shop www.veegee.com. They've a BUNCH
    from which to select. I've one which was
    dropped. May replace. Quicker than the
    digital I now have.

    A few outlets may be found by Googling
    for, veegee thermometers. Click on
    nova-tech; first Google page. Dan
     
  5. markbarendt

    markbarendt Subscriber

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    I just got 2 of the cheap ones and they seem to work fine.

    A bit of context for the whole thing though.

    I looked into getting my employer to buy a Fluke digital ray gun with temp probe, intrinsically safe for the areas I work in. The basic thermometer was $900, the calibration to make it read the "real temp" was another $220. We all carry some version of these temp guns and without the calibration switching from one to another there may be as much as 5 degrees difference at ~100.

    Most thermometers will be consistent, if used the same way each time, but any one specific thermometer will rarely match any other specific thermometer exactly.

    This is one reason why a friend of yours might get good results with Xtol at 68 degrees but at your house with your thermometer you need to use 70 degrees to get the same contrast. In reality the "real temp" of the chemical may be the same.

    In the real world, once you test a bit and figure out your system with a specific thermometer you are good to go.
     
  6. fotch

    fotch Member

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    I purchased a used like new Kodak Process Thermometer #3. Less than $20 if I recall. SS housing, impressive if nothing else. Suppose to be very accurate. The dial type that I use to use are get out of calibration to easily.
     
  7. PeteZ8

    PeteZ8 Member

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    I have a couple of the "Kodak Deluxe Thermometers". Albeit these are pretty long, they are super fast acting and the long length makes it easy to get an accurate reading quickly because the graduations are spaced pretty far apart. Both of these came in "lots" of darkroom equipment I have picked up but I highly recommend them if you can find one. I have several of the small thermometers and a dial thermometer that I never even pull out of the box. I find the small ones too fiddly, especially in larger beakers, and the dials far to cumbersome.

    Probably most comparable to the Patterson 12", but if you don't need color temperature range, the 9" looks like a nice unit too.

    By their very nature, a larger therometer should be more accurate. With more distance between the graduations visibility will be better and any manufacturing errors should be diluted over a longer distance. Same applies to temperature range. The less range, the higher the accuracy should be on a % basis.
     
  8. Ektagraphic

    Ektagraphic Member

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    I have a legacy pro that has done me well so far.
     
  9. Craig Swensson

    Craig Swensson Member

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    quote
    Am I just overanalyzing a trivial matter?


    Not trivial but could be overanalyzing at bit, try the local brew shop, temp is just as critical in making alcohol[and drinking]

    oh, you are in Alabama, might have to go to the woods:D
     
  10. Existing Light

    Existing Light Member

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    oops :smile:

    This is the patterson one http://www.freestylephoto.biz/381-Paterson-12-in.-Color-Thermometer

    Thanks for the feedback, guys.

    I would like to get in to doing color sometime in the future (perhaps in the next 6-9 months), so I'm thinking I might should just go ahead and get the Patterson if I'm going to order off Freestyle. I will take a look at the other thermometer suggestions as well before I make a decision.