Colour-review instructions can become ambiguous when a casual description of a lamp is used as though it defines the assessment method. Clarify the terms before comparing results.
Coats distinguishes a physical light source from an illuminant used to describe a specified spectral distribution in colour work. Coats — Differentiating Metamerism and Illuminants.
Describe the actual setup
For a hypothetical material review, record the equipment and conditions used by each party. Ask the technical reviewer which reference and method the comparison is intended to follow. Do not assume that two rooms described as daylight create equivalent evidence.
Keep observations tied to the setup
Record where a match appears acceptable and where a difference is seen. If the method changes, preserve that change with the result. A clear record helps explain disagreement without assigning fault from photographs alone.
Use the terminology to improve the review request. It does not replace a project-specific decision about relevant conditions or the physical references against which the materials will be assessed.
Source reviewed 25 October 2026. Practical interpretation and original illustrations by PLUSHIP / Qunhe; examples are illustrative.
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