Cheap WB References

Discussion in 'Photography Beginners' Forum' started by Helen B, Feb 16, 2008.

  1. Helen B

    Helen B TPF Noob!

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    A white balance reference is sometimes useful when setting custom white balance in camera or later in post processing. Various reference cards and devices can be purchased. I assembled a few, and compared them with the things I often use.

    It's often more important to get consistent white balance rather than technically accurate white balance. A consistent reference will help to normalize a set of photos before making adjustments to the aesthetically pleasing balance. It isn't always important, therefore, to have a technically perfect white reference.

    Here are the spectral characteristics of some commercial grey references.

    [​IMG]

    The Smethurst card is not supposed to be an 18% card - it is closer to 14.5%. The Macbeth reference is the middle step of the Macbeth three-step card.

    Next, white references.

    [​IMG]

    Though they all look far from white, in practice I've been happy with the white balance obtained from them all, with the Exception of the Portabrace.

    Finally, the cream of the crop. Free stuff.

    [​IMG]

    Look for kitchen towels or paper napkins that look clean and white. They are not likely to have lots of optical brighteners. Expanded polystyrene ("Styrofoam") is naturally white, and it makes a good reference. You can put a cup over your lens for an in-camera white balance, just like the rather more expensive ExpoDisc. You can also use polystyrene plates etc.

    Best,
    Helen
     
  2. Bifurcator

    Bifurcator TPF Noob!

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    Thanks Helen! Good info! :thumbup:
     
  3. Jedo_03

    Jedo_03 TPF Noob!

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    That settles a recent "debate" with a fellow enthusiast who believes that a high-tech grey card is superior for WB than a white object...
    Jedo
     
  4. tirediron

    tirediron Watch the Birdy! Staff Member Supporting Member

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    Excellent info as always Helen, much appreciated.
     
  5. Chris of Arabia

    Chris of Arabia Herding cats since 1988... Supporting Member

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    What did you measure these with? Not doubting the results, just wish to understand the process involved.
     
  6. Chris of Arabia

    Chris of Arabia Herding cats since 1988... Supporting Member

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    What did you measure these with? Not doubting the results, just wish to understand the process involved.
     
  7. Helen B

    Helen B TPF Noob!

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    They were measured with a calibrated Eye-One Pro using SpectraShop, then the data was exported to Excel. The i1 is a 45/0:c* spectrometer that measures internally in 3 nm bandwidths, and outputs in 10 nm bandwidths.

    Best,
    Helen

    *45/0:c means that the illumination for reflective samples is in a circumferential ring at 45° to the normal, and the receptor is on the normal.
     

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