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standard illuminant D65

[4.9.3.3] A representation of daylight at a correlated color temperature of approximately 6500 K. It is defined by its relative spectral power distribution over the range from 300 to 830 nm.*

Note: At present, no manufactured source for matching this illuminant has been recommended.

 

* Rea MS (ed.). The IESNA Lighting Handbook, 9th ed. New York: Illuminating Engineering Society of North America; 2000. Figure 4-3. 

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