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Gamut Index (Rg)

[4.3.1.33.3]

A measure of the average change in chroma produced by a test illuminant relative to a standardized reference illuminant for the 99 color evaluation samples specified in ANSI/IES TM-30-20, Technical Memorandum: IES Method for Evaluating Light Source Color Rendition.

Note: Values above 100 indicate an average increase in chroma; values less than 100 indicate an average decrease in chroma. Typical values: 80 to 120.

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