anyone calibrated a minolta colour meter?

Discussion in 'Lighting' started by wildtypitch, Jul 1, 2009.

  1. wildtypitch

    wildtypitch Member

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    I now have two inaccurate minolta 2f color meters. I've taken them apart and found one adjustment screw on the main body and six in the head behind the receptor. I've been told via the grapevine that these 6 screws are used to adjust (I tried the one on the body and it seemed to have no effect).
    Has anyone any experience with calibrating these things? I presume that the six screws are split 3 for each colour group high, mid and low points. I will get a known source light and then adjust for the high and lows using filtration between the source and meter.
    Anyone see any flaws?
     
  2. Kirk Keyes

    Kirk Keyes Member

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    You say they are inaccurate? How did you determine this?
     
  3. wildtypitch

    wildtypitch Member

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    1. By them not agreeing with eachother.
    2. By shooting test slides in various lighting situations and getting back results that are way out when larger filtration is required.
    3. Taking readings with the meter pointing to the camera as per instructions, the spot that I meter is not balanced in the slide.
     
  4. wildtypitch

    wildtypitch Member

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    1. Have two meters as stated, they are in disagrement (mayor).
    2. Test shoots under varying lighting situations have given results that are not blanced. I read using the meter pointing directly to the camera at the point that I want balanced as per instructions.

    Do you have any experience with adjusting this meter? Or have I described something that I'm doing wrong?
     
  5. Kirk Keyes

    Kirk Keyes Member

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    Could you describe the lighting conditions and how far off you think the meters are - both for the lighting conditions and between themselves?

    What readings do you get in sunlight in the middle of the day, and for a regular tungsten incandescent light with no other light sources?
     
  6. wildtypitch

    wildtypitch Member

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    ok i will . tugsen lighting with tungsten film. set on the meter. get results that without filtration are good, meter recomends another +86 blue fitration. tried both, meter is out. both are out by about 70 between hemselves. I hope you now understand that i am not a fool, so please if you know how to calibrate these meters then let me know. THANKS FOR THE EFFORT!
     
  7. epatsellis

    epatsellis Member

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    I would strongly urge sending the to Quality Light Metric, I'm sure they can get them calibrated quickly. If you are adamant about doing it yourself, be sure to find their information before you start, as you'll end up sending them there after you're done.

    Realistically, without calibrated light sources, a service manual and knowing what the test points and voltages are at the designated points on the curve, you'd be better off guessing.
     
  8. lucacasa

    lucacasa Member

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    Hi! I have the same problem, didi you find how to calibrate it? I tried with the screw but it's impossible withut a method...
     
  9. Leigh B

    Leigh B Member

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    Calibrating a color meter requires laboratory equipment that you don't have.

    Send it to a pro.

    - Leigh