Do CDS cells in Old light meters lose sesitivity?

Discussion in 'Miscellaneous Equipment' started by chip j, Jan 15, 2018.

  1. BrianShaw

    BrianShaw Member

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    Does he know which index mark on the dial to use with the 7.5 deg reading? Using the wrong mark is s rather common error.
     
  2. btaylor

    btaylor Subscriber

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    Yes, when I have been away from mine for awhile I sometimes need to refer to the manual to refresh my memory on the marks.
    Also common are analog light meters that have gone out of calibration, it's not a big deal. Like so many of the mechanical marvels we so enjoy on this forum service and calibration are often called for. George at Quality Light Metric is your man.
     
  3. OP
    OP
    chip j

    chip j Subscriber

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    Yes, I showed him exactly how to use it. I was there when he took readings.
     
  4. BrianShaw

    BrianShaw Member

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    Does it read low without the spot attachment, in either general coverage reflected or incidence modes?

    Did it read low when you last used it, before you gave it to your friend or is this a sudden change in the meters behaviour?
     
    Last edited: Jan 17, 2018
  5. paul ron

    paul ron Subscriber

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    the attachment has to be compensated for. its in the manual.
     
  6. trendland

    trendland Member

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    It shall be a logarithmic issue as far as I knew. The grandfather of an old fellow photographer/camera operator was one of the inventors. He told me there have been some patents of his grandpa (from the 30th I just guess).
    Hard to believe what he told me - but the family owned more than one factory - so it might be the truth.
    But it isn't linear (when your cell began to lose sensitifity AFTER DECADES)
    with regards
     
  7. Sirius Glass

    Sirius Glass Subscriber

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    Unless the attachment is properly compensated the reading will be off by about two stops. Test the meter without the spot meter attachment. The instructions are poorly written and it took me many readings and experimentation to finally get it right. That is why added the colored dots to the light meter.
     
  8. E. von Hoegh

    E. von Hoegh Member

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    Unless you are comparing it to a known accurate METER, without the 7.5 degree attachment, there's really no point.
     
  9. ic-racer

    ic-racer Member

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    I don't know about you all, but when my workplace gave me an iPhone I downloaded a meter program with the intent of getting rid of my very old (but still working fine) Sekonic meter. After a while I realized the iPhone meter didn't match any of my other meters and seemed to have some hysteresis in the response. So I just bought a new-to-me Sekonic meter yesterday.
     
  10. bdial

    bdial Subscriber

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    I have two different meter apps on my phone, they seem ok accuracy wise, but both are a bit fiddly to work to work with. Especially considering that before you even get making a reading you need to login on the phone then locate the app, then make sure it still has the right ISO, etc. Whereas with a meter you just point it at whatever and maybe push a button.
    The phone app does make a handy back-up though, my meters have a habit of not being with the particular kit I want to use, so rather than hunt it up, it's sometimes easier to use the phone.
     
  11. Sirius Glass

    Sirius Glass Subscriber

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    As bdial points out using a so called smart phone is often inconvenient. In this case a separate light meter is a much better solution.
     
  12. ic-racer

    ic-racer Member

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    I think the iPhone would be more convenient. For safety reasons, I don't hike without it and it is ten times smaller by volume than the Sekonic meter I just bought. I know a lot of you use the big Sekonic meters, because I spent a week scanning this forum and LF and many of you shared information on your favorite meter. For example I got the Sekonic 558 and presumably Leigh has two of these. I feel like I"m going to need a separate back pack just to carry the meter. Sekonic 558 = 170mm x 90mm x 48mm = 734cc whereas iPhone = 140mm x 7mm x 65mm = 64cc
     
    Last edited: Jan 17, 2018
  13. Sirius Glass

    Sirius Glass Subscriber

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