Lightness color difference metrics

Next the CIELAB coordinates are converted to differences in metric lightness, metric chroma, and metric hue (not hue angle), AL, AC, AH, respectively. By themselves, these parameters define a spherical color difference volume in the rectangular coordinates (L, C, H) with a radius of AEab ... 

Andon A system used to notify others of equipment or process problems. Often a light pole mounted on operational equipment that has three different colored lights. The lights, which signal machine condition, can be activated manually or via the machine controls. Benchmarking A formal or informal method of comparing and sharing business processes and performance metric results in order to drive business improvement. 

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