Light Sources | SPD Curves | National Gallery, London

Find the chromaticity xy co-ordinates of the test source from its calculated CIE 1931 color space XYZ values.
Determine the correlated color temperature (CCT) of the test source and select the appropriate black body reference source.
Illuminate the first eight standard Munsel samples, alternately using both sources.
Find the chromaticity co-ordinates of the light reflected by each sample in the CIE 1964 color space.
Chromatically adapt each sample by a von Kries transform.
For each sample, calculate the Euclidean distance $Δ E i$ between the pair of co-ordinates.
Calculate the special (i.e., particular) CRI using the formula $R i = 100 - 4.6Δ E i$
Find the general CRI (R_a) by calculating the arithmetic mean of the first 8 special CRIs.
See wikipedia for more information.

		TCS01	TCS02	TCS03	TCS04	TCS05	TCS06	TCS07	TCS08	TCS09	TCS10	TCS11	TCS12	TCS13	TCS14
Reference	U	36.15	16.94	-10.00	-36.75	-31.28	-22.09	11.92	35.54	118.04	29.99	-46.81	-29.77	33.28	-7.76
	V	6.12	16.87	25.87	13.20	-5.27	-22.74	-20.21	-12.17	6.14	36.65	11.00	-34.13	12.91	13.85
	W	61.54	60.37	61.17	59.35	60.42	59.45	60.18	62.56	42.18	81.50	49.97	27.14	80.28	39.78
Illuminant	U	36.67	17.57	-10.49	-36.99	-31.63	-22.88	11.32	34.43	115.05	30.49	-46.94	-30.68	34.08	-8.21
	V	6.13	16.44	25.59	12.47	-5.39	-22.38	-19.58	-11.84	6.38	36.08	10.38	-33.81	12.44	13.74
	W	61.50	60.24	61.23	59.43	60.52	59.58	60.19	62.48	42.01	81.34	50.10	27.42	80.12	39.81
ΔE_UVW		0.52	0.78	0.57	0.78	0.39	0.88	0.87	1.17	3.00	0.77	0.64	1.00	0.94	0.47
R_i		97.60	96.43	97.37	96.42	98.22	95.96	96.00	94.62	86.18	96.48	97.04	95.38	95.69	97.83

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