White Balance
Definition
A camera setting that corrects for the colour temperature of the ambient illuminant, ensuring neutral colours render as neutral. Manual white balance referenced to a grey card is the forensic standard.
- Purpose
- Corrects for ambient illuminant colour temperature
- Forensic standard
- Manual white balance referenced to a grey card
- Effect if wrong
- Neutral colours render with a colour cast
- Field
- Forensic photography
Common questions
Why is manual white balance preferred over automatic white balance in forensic photography?+
Automatic settings can shift between frames of the same scene as the camera reinterprets the lighting, which undermines colour consistency for comparison purposes; a manual setting locked to a grey card keeps colour rendering stable across the whole documentation set.
What happens if white balance is set incorrectly when photographing evidence such as bruising or bloodstains?+
A colour cast can make the evidence appear a different hue than it actually is, potentially affecting interpretation of injury age or stain colour, so an incorrect white balance can undermine the evidentiary value of the image.
Related terms
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- Depth of Field (DoF)
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- Diffraction Limit
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- Dynamic Range
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- ISO
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