The visual mechanism of a normal observer is so constructed that objects keep nearly their daylight colors even when the illuminant departs markedly from average daylight. The processes by means of which the observer adapts to the illuminant or discounts most of the effect of a nondaylight illuminant are complicated; they are known to be partly retinal and partly cortical. By taking into account the various fragments of both qualitative and quantitative information to be found in the literature, relations have been formulated by means of which it is possible to compute approximately the hue, saturation, and lightness (tint, value) of a surface color from the tristimulus specifications of the light reflected from the surface and of the light reflected from the background against which it is viewed. Preliminary observations of 15 surfaces under each of 5 different illuminants have demonstrated the adequacy of the formulation and have led to an approximate evaluation of the constants appearing in it. More detailed and extensive observations have been carried out in the psychological laboratories of Bryn Mawr College. and these observations have resulted in an improved formulation.
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Numbers preceded by the “less-than” (<) sign indicate spectral transmissions greater than those possessed by the respective filters.
Table VI
Trilinear coordinates (r,g) of the light reflected from each sample and the apparent reflectances (A) of the samples for each of the five illuminants used.
Abbot-Priest Sunlight
Red Illuminant
Yellow Illuminant
Green Illuminant
Blue Illuminant
Sample
r
g
A
r
g
A
r
g
A
r
g
A
r
g
A
MgO
0.458
0.458
1.000
0.958
0.042
1.000
0.705
0.295
1.000
0.372
0.613
1.000
0.237
0.351
1.000
R3/7
.606
.342
.087
.961
.039
.276
.792
.208
.151
.390
.597
.049
.243
.338
.048
R5/10
.628
.327
.221
.959
.041
.706
.796
.204
.404
.391
.595
.110
.241
.344
.110
R7/6
.527
.408
.459
.958
.042
.781
.744
.255
.618
.380
.606
.357
.240
.347
.346
YR4/5
.574
.394
.163
.959
.041
.297
.735
.265
.246
.401
.589
.110
.248
.365
.069
Y5/7
.525
.448
.241
.957
.043
.272
.700
.299
.288
.393
.598
.221
.254
.373
.097
Y7/8
.532
.449
.490
.958
.042
.577
.703
.296
.588
.393
.598
.455
.265
.398
.159
G3/4
.437
.490
.094
.961
.039
.072
.686
.313
.078
.367
.619
.107
.236
.369
.093
G5/7
.407
.539
.285
.953
.047
.087
.637
.362
.171
.362
.624
.377
.237
.413
.267
G7/7
.439
.497
.522
.956
.044
.329
.677
.322
.428
.367
.619
.596
.237
.384
.493
B3/5
.374
.485
.114
.958
.042
.064
.685
.314
.072
.351
.629
.133
.232
.353
.217
B5/6
.386
.491
.277
.959
.041
.161
.684
.315
.185
.354
.627
.324
.232
.363
.472
B7/4
.427
.478
.531
.957
.043
.381
.690
.309
.445
.365
.619
.581
.236
.356
.642
P3/6
.440
.423
.108
.962
.038
.153
.730
.270
.119
.370
.612
.097
.237
.325
.153
P5/6
.456
.434
.253
.961
.039
.359
.731
.269
.273
.370
.614
.235
.236
.337
.310
PB7/4
.428
.467
.458
.960
.040
.428
.704
.294
.405
.364
.619
.485
.236
.350
.600
Table VII
Constants used in computing the trilinear coordinates (rn,gn,bn) of the achromatic points for the five illuminants studied (Eq. 3).
This constant refers to the dark background (A0=0.10); the one given just above to the light background (A0=0.80).
Table IX
Computed hues, lightnesses and saturations for 3 hypothetical nonselective samples for both light and dark backgrounds, for the 5 illuminants, and for 4 observing situations (Cases 1 to 4).
Illuminant
A0
Sample
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Abbot-Priest sunlight
0.80
N 2/0
RB 0.2/0.2
RB 0.3/0.2
N /0.0
YR /1.1
N 5/0
RB 3.5/0.1
RB 5.3/0.1
N /0.0
YR /1.1
N 9/0
N 8.8/0.0
Y 9.4/0.1
N /0.0
YR /1.1
.10
N 2/0
RB 0.3/0.1
RB 0.6/0.1
N /0.0
YR /1.1
N 5/0
N 5.2/0.0
N 6.9/0.0
N /0.0
YR /1.1
N 9/0
YG 9.4/0.1
YG 9.7/0.1
N /0.0
YR /1.1
Red
.80
N 2/0
B 0.2/6.3
B 0.3/5.2
N /0.0
YR /33.9
N 5/0
RB 3.5/1.8
R 5.3/1.7
N /0.0
YR /33.9
N 9/0
YR 8.7/6.8
YR 9.4/5.8
N /0.0
YR /33.9
.10
N 2/0
B 0.3/4.3
B 0.6/2.3
N /0.0
YR /33.9
N 5/0
YR 5.0/4.6
YR 6.9/5.1
N /0.0
YR /33.9
N 9/0
YR 9.3/12.0
YR 9.7/7.8
N /0.0
YR /33.9
Yellow
.80
N 2/0
B 0.2/2.3
B 0.3/2.0
N /0.0
YR /16.5
N 5/0
RB 3.5/0.9
R 5.3/0.6
N /0.0
YR /16.5
N 9/0
Y 8.8/1.9
Y 9.4/1.6
N /0.0
YR /16.5
.10
N 2/0
RB 0.3/1.7
RB 0.6/1.1
N /0.0
YR /16.5
N 5/0
YR 5.1/1.3
Y 6.9/1.4
N /0.0
YR /16.5
N 9/0
Y 9.4/3.6
Y 9.7/2.2
N /0.0
YR /16.5
Green
.80
N 2/0
RB 0.2/1.3
RB 0.3/1.1
N /0.0
G /8.8
N 5/0
RB 3.5/0.5
RB 5.3/0.2
N /0.0
G /8.8
N 9/0
YG 8.8/0.7
YG 9.4/0.6
N /0.0
G /8.8
.10
N 2/0
RB 0.3/0.9
RB 0.6/0.6
N /0.0
G /8.8
N 5/0
YG 5.2/0.4
YG 6.9/0.4
N /0.0
G /8.8
N 9/0
YG 9.4/1.6
YG 9.7/0.9
N /0.0
G /8.8
Blue
.80
N 2/0
RB 0.2/2.5
RB 0.3/1.9
N /0.0
RB /20.0
N 5/0
RB 3.5/0.9
RB 5.3/0.9
N /0.0
RB /20.0
N 9/0
B 8.8/4.7
B 9.4/3.4
N /0.0
RB /20.0
.10
N 2/0
RB 0.3/1.0
RB 0.6/0.9
N /0.0
RB /20.0
N 5/0
B 5.2/1.7
B 6.9/1.7
N /0.0
RB /20.0
N 9/0
B 9.4/5.5
B 9.7/2.8
N /0.0
RB /20.0
Table X
Comparison of observed and computed color descriptions. (Hue, lightness and saturation (HL/S) of the 15 selective samples studied. Illuminant: Abbot-Priest sunlight taken as representative of south daylight.)
Sample
Average Observed ValuesHL/S
Individual Observer Range ΔHΔL/ΔS
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Light background (A0=0.80)
R 3/7
R 2.6/5.1
R 1–3/2–7
YR 1.6/9.6
YR 2.6/9.6
YR /9.5
YR /10.6
R 5/10
R 5.2/10
R 4–6/10
YR 4.0/10.9
YR 5.8/10.9
YR /10.9
YR /12.0
R 7/6
R 6.9/5.8
RB-YR 5–8/3–8
YR 6.8/4.4
YR 8.2/4.4
YR /4.4
YR /5.5
YR 4/5
YR 3.8/4.8
YR 3–5/1–7
YR 3.0/7.1
YR 4.7/7.1
YR /7.1
YR /8.3
Y 5/7
gY 4.6/4.4
Y-YG 4–5/2–6
Y 4.3/4.4
Y 6.1/4.4
Y /4.4
Y /5.4
Y 7/8
Y 6.7/9.4
Y 6–8/9–10
Y 7.1/4.9
Y 8.3/4.9
Y /5.0
Y /5.9
G 3/4
yG 2.0/2.9
YG-G 1–3/1–6
G 1.7/1.9
G 2.8/1.9
G /2.0
YG /1.3
G 5/7
G 5.3/9.8
G 4–6/9–10
G 4.9/5.0
G 6.7/5.0
G /5.0
G /4.2
G 7/7
yG 7.3/5.2
YG-G 7–8/4–8
G 7.4/2.4
G 8.5/2.4
G /2.4
YG /1.9
B 3/5
B 3.0/6.2
B 2–4/5–7
B 2.1/5.3
B 3.4/5.3
B /5.2
B /4.2
B 5/6
B 4.9/7.9
B 4–6/7–9
BG 4.8/4.4
BG 6.6/4.4
BG /4.4
B /3.3
B 7/4
gB 7.3/3.4
BG-B 7–8/1–8
BG 7.4/1.9
BG 8.6/1.9
BG /1.9
BG /0.8
P 3/6
RB 2.9/6.8
RB 2–4/6–8
RB 2.0/3.4
RB 3.3/3.4
RB /3.3
RB /3.3
P 5/6
RB 5.1/5.3
RB 5–6/4–8
RB 4.5/1.8
RB 6.3/1.8
RB /1.8
R /2.2
PB 7/4
B 6.8/3.6
rB-B 6–7/1–8
B 6.8/1.9
B 8.1/1.9
B /1.9
RB /1.0
Dark background (A0=0.10)
R 3/7
R 3.1/5.1
R 1–5/3–8
YR 2.7/9.6
YR 4.2/9.6
YR /9.5
YR /10.6
R 5/10
R 6.0/10
RB-R 5–7/10
YR 5.7/11.0
YR 7.3/10.9
YR /10.9
YR /12.0
R 7/6
R 7.4/6.8
RB-YR 7–9/3–9
YR 8.1/4.4
YR 8.9/4.4
YR /4.4
YR /5.5
YR 4/5
YR 4.1/5.9
YR 2–5/2–9
YR 4.7/7.1
YR 6.4/7.1
YR /7.1
YR /8.3
Y 5/7
Y 4.6/4.5
Y 2–6/2–6
Y 6.0/4.5
Y 7.5/4.4
Y /4.4
Y /5.4
Y 7/8
Y 7.4/9.9
Y 6–9/9–11
Y 8.3/4.9
Y 9.0/5.0
Y /5.0
Y /5.9
G 3/4
G 2.4/2.2
G 1–4/2–4
G 2.8/1.9
G 4.5/1.9
G /2.0
YG /1.3
G 5/7
G 5.7/9.0
G 4–8/8–10
G 6.6/5.0
G 7.9/5.0
G /5.0
G /4.2
G 7/7
G 7.4/4.7
YG-BG 6–9/3–8
G 8.5/2.4
G 9.2/2.4
G /2.4
YG /1.9
B 3/5
B 3.2/7.2
B 2–4/7–8
B 3.3/5.3
B 5.1/5.3
B /5.2
B /4.2
B 5/6
B 5.4/6.8
B 4–6/5–8
BG 6.4/4.3
BG 7.9/4.3
BG /4.4
B /3.3
B 7/4
gB 7.6/1.8
BG-B 5–10/1–4
BG 8.5/1.9
BG 9.2/1.9
BG /1.9
BG /0.8
P 3/6
RB 3.1/5.7
RB 2–4/4–9
RB 3.2/3.4
RB 4.9/3.4
RB /3.3
RB /3.3
P 5/6
RB 5.2/3.8
RB 4–6/1–7
RB 6.1/1.7
RB 7.6/1.7
RB /1.8
R /2.2
PB 7/4
rB 7.2/1.7
RB-B 5–8/1–3
B 8.6/1.9
B 8.9/1.8
B /1.9
RB /1.0
Table XI
Comparison of observed and computed color descriptions. Hue, lightness and saturation (HL/S) of the 15 selective samples studied under the 4 chromatic illuminants; see Table V.
Sample
Average Observed ValuesHL/S
Individual Observer Range ΔHΔL/ΔS
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Red illuminant, light background (A0=0.80)
R 3/7
bR 4.0/1.2
RB-YR 3–5/0–4
R 4.7/1.7
YR 6.6/3.0
YR /0.2
YR /34.1
R 5/10
rYR 9.2/1.4
R-rY 8–10/0–4
YR 8.5/6.6
YR 9.3/5.9
YR /0.1
YR /33.9
R 7/6
YR 9.7/1.3
yR-rY 8–10/0–4
YR 9.0/7.0
YR 9.5/6.1
N /0.0
YR /33.9
YR 4/5
bR 4.2/1.1
RB-YR 3–5/0–4
R 5.0/1.9
YR 6.8/3.1
YR /0.1
YR /33.9
Y 5/7
bR 3.9/1.0
RB-YR 3–5/0–4
R 4.6/1.5
YR 6.5/2.7
BG /0.1
YR /33.8
Y 7/8
yR 7.5/1.0
R-YR 6–9/0–2
YR 7.7/5.3
YR 8.8/5.3
N /0.0
YR /33.9
G 3/4
B 1.1/1.9
BG-BR 0–2/0–6
B 1.1/4.9
B 2.1/3.3
YR /0.2
YR /34.1
G 5/7
B 1.4/1.9
BG-RB 1–2/0–6
B 1.5/4.8
B 2.5/3.0
BG /0.4
YR /33.6
G 7/7
yR 4.6/1.1
R-YR 4–6/0–4
R 5.4/2.0
YR 7.1/3.3
BG /0.1
YR /33.7
B 3/5
gB 1.1/1.8
BG-B 0–2/0–6
B 0.9/5.3
B 1.6/3.6
N /0.0
YR /33.9
B 5/6
RB 2.3/1.4
B-R 1–4/0–6
B 2.9/2.6
RB 4.6/1.5
YR /0.1
YR /33.9
B 7/4
yR 5.2/1.0
R-YR 4–6/0–4
YR 6.0/2.7
YR 7.6/3.8
BG /0.1
YR /33.8
P 3/6
RB 2.3/1.5
B-YR 1–4/0–6
B 2.7/2.7
RB 4.4/1.4
YR /0.3
YR /34.2
P 5/6
bR 5.0/1.0
RB-YR 4–6/0–4
YR 5.8/2.8
YR 7.4/3.9
YR /0.2
YR /34.1
PB 7/4
R 5.8/1.3
RB-YR 5–7/0–4
YR 6.5/3.6
YR 7.9/4.3
YR /0.1
YR /34.0
Red illuminant, dark background (A0=0.10)
R 3/7
YR 5.5/3.4
YR 5–6/2–5
YR 6.3/7.0
YR 7.8/6.3
YR /0.2
YR /34.1
R 5/10
YR 9.7/6.3
YR 7–11/3–12
YR 9.2/11.8
YR 9.6/7.8
YR /0.1
YR /33.9
R 7/6
YR 9.8/6.3
YR 7–11/3–12
YR 9.4/12.2
YR 9.8/7.8
N /0.0
YR /33.9
YR 4/5
YR 6.3/4.1
YR 5–7/3–6
YR 6.6/7.1
YR 8.0/6.1
YR /0.1
YR /33.9
Y 5/7
YR 6.0/3.4
YR 5–8/2–5
YR 6.2/6.5
YR 7.8/6.0
BG /0.1
YR /33.8
Y 7/8
YR 9.0/6.0
YR 7–10/3–11
YR 8.6/10.7
YR 9.3/7.5
N /0.0
YR /33.9
G 3/4
RB 1.3/0.4
RB-R 1–2/0–2
RB 1.9/1.9
R 3.5/2.0
YR /0.2
YR /34.1
G 5/7
R 1.8/0.6
RB-R 1–3/0–4
RB 2.4/1.5
YR 4.2/2.0
BG /0.4
YR /33.6
G 7/7
YR 6.7/3.9
YR 6–8/3–6
YR 6.9/7.6
YR 8.3/6.2
BG /0.1
YR /33.7
B 3/5
RB 1.0/0.6
B-RB 0–2/0–4
B 1.6/2.3
R 3.0/1.5
N /0.0
YR /33.9
B 5/6
YR 3.7/1.7
R-YG 3–4/1–4
YR 4.4/3.5
YR 6.3/4.4
YR /0.1
YR /33.9
B 7/4
YR 7.5/4.6
YR 6–8/3–8
YR 7.4/8.4
YR 8.6/6.7
BG /0.1
YR /33.8
P 3/6
rYR 3.8/2.0
R-YR 3–4/1–4
YR 4.2/3.5
YR 6.1/4.4
YR /0.3
YR /34.2
P 5/6
YR 6.9/4.2
YR 5–8/2–8
YR 7.2/8.4
YR 8.5/6.8
YR /0.2
YR /34.1
PB 7/4
YR 7.9/5.0
YR 6–9/3–10
YR 7.8/9.4
YR 8.8/7.2
YR /0.1
YR /34.0
Yellow illuminant, light background (A0=0.80)
R 3/7
rBR 3.8/10.0
RB-R 3–6/4–16
R 2.8/6.3
R 4.4/6.5
YR /6.2
YR /22.4
R 5/10
yR 6.8/9.7
R-YR 5–9/5–16
YR 6.3/7.3
YR 7.8/7.5
YR /6.4
YR /22.7
R 7/6
rYR 8.3/6.1
R-Y 8–10/3–10
YR 8.0/4.2
YR 9.0/4.1
R /2.8
YR /19.1
YR 4/5
bR 4.4/3.3
RB-Y 3–5/1–4
R 4.3/2.6
R 6.2/2.8
YR /2.1
YR /18.5
Y 5/7
YG 4.8/0.2
Y-G 4–6/0–1
RB 4.9/0.4
YR 6.7/0.5
BG /0.3
YR /16.3
Y 7/8
gY 8.3/0.4
Y-YG 8–10/0–1
Y 7.8/1.4
Y 8.8/1.4
BG /0.1
YR /16.4
G 3/4
bRB 1.5/4.2
B-RB 1–2/0–8
B 1.3/2.6
B 2.1/1.9
BG /1.3
YR /15.2
G 5/7
gBG 3.8/6.1
G-B 3–6/3–8
BG 3.1/4.8
BG 4.8/4.4
BG /4.8
YR /12.1
G 7/7
yG 6.4/4.3
YG-G 5–7/2–8
G 6.5/1.1
G 7.9/1.1
BG /1.9
YR /14.7
B 3/5
bRB 1.5/4.7
B-RB 1–2/0–10
B 1.2/2.6
B 1.9/2.1
BG /1.4
YR /15.2
B 5/6
gB 3.1/1.4
BG-RB 2–4/0–3
B 3.3/1.7
BG 5.1/1.0
BG /1.4
YR /15.1
B 7/4
yG 6.7/2.7
YG-G 5–7/1–4
YG 6.6/0.4
YG 8.0/0.5
BG /1.0
YR /15.5
P 3/6
rRB 2.5/5.5
RB-YR 2–3/2–10
RB 2.2/1.8
R 3.5/2.1
YR /1.8
YR /18.2
P 5/6
bR 4.7/3.3
RB-Y 4–6/1–4
R 4.7/2.3
YR 6.5/2.6
YR /1.8
YR /18.2
PB 7/4
YG 6.2/0.2
Y-G 5–7/0–1
YR 6.3/0.9
YR 7.8/1.1
RB /0.1
YR /16.5
Yellow illuminant, dark background (A0=0.10)
R 3/7
bR 4.9/8.4
RB-R 4–6/7–12
YR 4.2/7.0
YR 6.1/7.2
YR /6.2
YR /22.4
R 5/10
rYR 7.7/10.4
R-YR 6–10/8–16
YR 7.6/8.5
YR 8.7/8.0
YR /6.4
YR /22.7
R 7/6
yYR 8.6/8.9
R-Y 7–10/6–16
YR 8.9/5.6
YR 9.4/4.6
R /2.8
YR /19.1
YR 4/5
YR 5.3/5.2
YR 3–6/4–7
YR 5.9/3.6
YR 7.6/3.5
YR /2.1
YR /18.5
Y 5/7
gY 5.8/3.5
Y-YG 5–6/1–6
Y 6.5/1.8
Y 8.0/3.6
BG /0.3
YR /16.3
Y 7/8
gY 8.4/6.6
Y-yYG 7–10/2–14
Y 8.8/3.1
Y 9.4/2.0
BG /0.1
YR /16.4
G 3/4
yG 1.5/0.6
YG-G 1–2/0–2
B 2.2/1.4
BG 3.6/0.7
BG /1.3
YR /15.2
G 5/7
G 4.7/8.6
G 4–6/7–12
G 4.7/3.8
G 6.5/3.7
BG /4.8
YR /12.1
G 7/7
gYG 7.2/6.6
YG-G 6–8/4–10
YG 7.8/1.9
YG 8.8/1.4
BG /1.9
YR /14.7
B 3/5
yG 1.4/0.4
YG-G 1–2/0–2
B 2.0/1.4
BG 3.4/0.9
BG /1.4
YR /15.2
B 5/6
gYG 4.2/4.3
YG-G 3–5/3–6
YG 5.0/0.7
YG 6.8/0.7
BG /1.4
YR /15.1
B 7/4
YG 7.2/5.3
Y-G 6–8/2–8
Y 7.9/2.2
Y 8.9/1.4
BG /1.0
YR /15.5
P 3/6
rYR 3.1/3.4
R-YR 2–5/2–6
R 3.4/2.4
YR 5.2/2.6
YR /1.8
YR /18.2
P 5/6
YR 5.3/4.9
YR 4–6/3–6
YR 6.3/3.6
YR 7.8/3.3
YR /1.8
YR /18.2
PB 7/4
Y 7.0/4.7
Y-gY 6–8/2–8
Y 7.6/2.6
Y 8.7/1.9
RB /0.1
YR /16.5
Green illuminant, light background (A0=0.80)
R 3/7
RB 1.0/3.3
RB 1–2/0–8
R 0.5/2.1
R 1.0/1.8
YR /1.2
G /7.8
R 5/10
R 2.3/2.4
RB-yG 2–3/0–6
R 2.0/1.9
R 3.2/1.7
YR /1.3
G /7.7
R 7/6
rY 5.5/1.4
R-G 4–7/0–4
YR 5.8/0.5
YR 7.4/0.5
YR /0.5
G /8.4
YR 4/5
YR 2.5/2.8
R-YG 2–3/0–6
R 2.0/2.4
R 3.2/2.2
YR /1.9
YG /7.4
Y 5/7
gY 4.1/2.8
YR-YG 3–5/1–4
YR 4.0/1.5
YR 5.8/1.3
YR /1.3
YG /7.9
Y 7/8
gY 7.1/5.1
Y-YG 6–8/3–8
YR 6.7/1.3
YR 8.1/1.3
YR /1.3
YG /7.9
G 3/4
B 2.3/1.8
G-RB 2–3/0–6
RB 2.0/0.7
RB 3.2/0.4
G /0.4
G /9.1
G 5/7
G 5.8/2.4
G 4–8/0–4
G 6.0/0.8
G 7.6/0.9
G /0.7
G /9.4
G 7/7
G 8.3/0.9
G 7–9/0–2
G 7.9/0.8
G 8.9/0.9
G /0.4
G /9.1
B 3/5
B 2.8/3.8
B 2–4/2–6
B 2.4/1.3
BG 3.9/1.3
BG /1.3
G /9.8
B 5/6
B 5.1/3.9
B 3–6/1–7
BG 5.4/1.1
BG7.1/1.2
BG /1.2
G /9.6
B 7/4
B 8.0/0.5
BG-B 6–9/0–2
G 7.8/0.8
G 8.8/0.9
BG /0.5
G /9.1
P 3/6
bRB 2.3/2.1
B-RB 2–3/0–6
RB 1.7/1.1
RB 2.8/0.8
B-RB /0.2
G /8.7
P 5/6
B 4.1/0.8
BG-RB 2–5/0–4
RB 4.2/0.4
B 6.1/0.1
BG /0.1
G /8.8
PB 7/4
B 7.2/1.0
B 6–8/0–2
G 7.0/0.7
G 8.3/0.7
BG /0.5
G /9.1
Green illuminant, dark background (A0=0.10)
R 3/7
bR 1.0/2.2
RB-R 0–2/0–6
R 1.0/1.7
R 1.9/1.4
YR /1.2
G /7.8
R 5/10
yYR 2.9/2.4
YR-Y 2–6/1–4
YR 3.2/1.4
YR 4.9/1.3
YR /1.3
G /7.7
R 7/6
gY 7.7/3.6
Y-YG 6–10/1–10
YG 7.2/0.9
Y 8.4/0.8
YR /0.5
G /8.4
YR 4/5
yYR 3.6/3.8
YR-Y 3–6/2–6
YR 3.2/2.0
YR 4.9/1.9
YR /1.9
YG /7.4
Y 5/7
gY 6.1/4.8
Y-YG 4–8/2–10
Y 5.6/1.4
Y 7.3/1.3
YR /1.3
YG /7.9
Y 7/8
Y 8.5/6.7
Y 8–12/3–16
Y 8.0/1.6
Y 8.9/1.4
YR /1.3
YG /7.9
G 3/4
G 2.8/1.2
G 2–4/0–4
BG 3.2/0.3
G 4.8/0.4
G /0.4
G /9.1
G 5/7
yG 7.7/4.4
YG-G 7–10/2–10
G 7.4/1.6
G 8.6/1.3
G /0.7
G /9.4
G 7/7
gYG 9.3/4.6
YG-G 9–12/1–12
YG 8.8/1.7
YG 9.4/1.2
G /0.4
G /9.1
B 3/5
gB 3.7/3.2
BG-B 3–4/2–6
BG 3.8/1.3
BG 5.6/1.4
BG /1.3
G /9.8
B 5/6
gB 7.2/4.0
G-B 6–10/2–10
G 7.0/1.7
G 8.2/1.5
BG /1.2
G /9.6
B 7/4
yG 9.2/4.2
YG-G 8–12/1–12
YG 8.7/1.6
YG 9.4/1.2
BG /0.5
G /9.1
P 3/6
RB 2.4/0.5
RB 1–4/0–4
RB 2.8/0.4
B-RB 4.6/0.2
B-RB /0.2
G /8.7
P 5/6
bG 5.9/2.0
G-BG 4–8/0–6
YG 5.7/0.6
YG 7.5/0.6
BG /0.1
G /8.8
PB 7/4
G 8.7/6.1
YG-BG 8–12/2–12
YG 8.2/1.5
G 9.0/1.0
BG /0.5
G /9.1
Blue illuminant, light background (A0=0.80)
R 3/7
rRB 1.4/1.8
RB-R 1–2/0–6
RB 0.5/2.7
RB 1.0/2.1
R /0.8
RB /20.3
R 5/10
bR 3.0/3.6
RB-R 3/2-6
RB 2.0/1.6
RB 3.3/1.3
R /0.4
RB /20.1
R 7/6
RB 5.9/3.1
RB-rRB 5–7/1–5
RB 5.7/1.3
RB 7.3/1.8
R /0.3
RB /20.0
YR 4/5
R 2.4/2.5
RB-YR 2–3/1–4
RB 1.1/0.2
Y 1.8/0.6
YG /1.5
RB /18.5
Y 5/7
rYR 3.5/2.8
RB-Y 3–4/1–4
YG 1.7/1.0
YG 2.9/1.6
YG /2.4
RB /17.6
Y 7/8
yYR 5.4/4.6
R-Y 4–6/1–6
YG 2.9/3.8
YG 4.6/3.9
YG /4.6
B /15.6
G 3/4
bRB 2.2/0.5
B-RB 2-3/0-2
B 1.6/0.5
YG 2.8/0.3
YG /1.2
B /19.0
G 5/7
yG 5.1/3.8
YG-BG 4–6/2–5
YG 4.7/3.5
YG 6.5/3.4
YG /4.4
B /16.7
G 7/7
yG 7.6/1.5
Y-G 6–9/0–4
BG 7.1/1.9
BG 8.4/2.1
YG /2.3
B /18.2
B 3/5
B 3.8/2.2
B 3–4/0–4
RB 3.9/0.9
RB 5.7/1.2
B /0.3
RB /20.2
B 5/6
gB 6.2/4.4
BG-B 5–7/2–6
B 6.9/2.1
B 8.2/2.3
G /0.7
RB /19.6
B 7/4
B 8.3/2.2
G-B 7–9/1–4
B 8.2/3.5
B 9.1/3.1
YG /0.3
RB /19.7
P 3/6
rB 3.0/3.4
B-RB 2–4/0–4
RB 2.8/2.8
RB 4.4/2.6
RB /1.8
RB /21.4
P 5/6
rB 4.8/2.8
B-rRB 4–5/0–5
RB 5.3/2.0
RB 6.9/2.5
RB /1.0
RB /20.8
PB 7/4
B 7.9/2.3
B 6–9/1–4
B 7.9/3.5
B 8.9/3.1
RB /0.1
RB /20.1
Blue illuminant, dark background (A0=0.10)
R 3/7
bR 1.2/2.0
RB-R 0–2/0–4
RB 1.0/1.7
RB 1.8/1.6
R /0.8
RB /20.3
R 5/10
rRB 3.3/4.2
RB-R 2–4/1–6
RB 3.2/1.3
RB 4.9/1.4
R /0.4
RB /20.1
R 7/6
rRB 7.2/2.5
RB-R 6–8/0–4
B 7.2/3.1
B 8.4/2.3
R /0.3
RB /20.0
YR 4/5
YR 2.7/3.3
rYR-YR 2–4/2–5
Y 2.0/1.0
Y 3.3/0.8
YG /1.5
RB /18.5
Y 5/7
yYR 3.9/4.2
YR-Y 3–5/3–5
YG 2.9/1.7
YG 4.6/1.5
YG /2.4
RB /17.6
Y 7/8
rY 6.2/6.2
YR-Y 5–7/4–8
YG 4.5/3.4
YG 6.2/3.3
YG /4.6
B /15.6
G 3/4
yG 2.7/1.7
YG-G 2–4/1–3
YG 2.8/0.4
G 4.4/0.5
YG /1.2
B /19.0
G 5/7
yG 6.4/5.1
YG-G 6–7/4–8
G 6.3/3.4
G 7.8/3.4
YG /4.4
B /16.7
G 7/7
gBG 8.3/2.1
G-B 8–9/1–8
BG 8.3/3.7
BG 9.1/2.2
YG /2.3
B /18.2
B 3/5
B 5.1/5.1
gB-B 4–6/4–8
B 5.6/2.2
B 7.2/2.0
B /0.3
RB /20.2
B 5/6
B 7.3/5.5
B 7–8/4–10
B 8.2/4.1
B 9.0/2.4
G /0.7
RB /19.6
B 7/4
B 9.0/3.4
B 8–10/1–10
B 9.0/5.1
B 9.5/2.6
YG /0.3
RB /19.7
P 3/6
bRB 4.1/4.2
B-RB 3–5/2–8
RB 4.3/2.9
RB 6.1/3.1
RB /1.8
RB /21.4
P 5/6
rB 6.3/4.4
B-RB 6–7/3–8
B 6.8/3.7
RB 8.1/2.9
RB /1.0
RB /20.8
PB 7/4
B 8.7/3.9
B 8–10/2–10
B 8.9/5.2
B 9.4/2.8
RB /0.1
RB /20.1
Table XII
Number of sample-illuminant-background combinations correct.
Illuminant
Apparent Reflectance of BackgroundA0
Number Correct
Case 3
Case 4
Case 2
Case 1
South
0.80
12 15/7
12 10/7
12 /7
11 /5
daylight
.10
12 14/7
12 8/7
12 /7
11 /6
Red
.80
15 15/12
15 7/12
15 /15
11 /0
.10
15 15/11
14 7/13
9 /3
12 /0
Yellow
.80
14 15/13
14 9/14
10 /15
5 /0
.10
12 15/12
12 6/10
5 /3
5 /0
Green
.80
10 15/13
9 12/13
10 /13
7 /2
.10
14 15/12
14 12/10
10 /8
8 /8
Blue
.80
11 11/14
10 12/14
7 /10
8 /0
.10
11 15/9
11 9/9
8/8
6/0
Total
.80
62 71/59
60 50/60
54 /60
42 /7
.10
64 74/51
63 42/49
44 /29
42 /14
Grand total correct
126 145/110
123 92/109
98 /89
84 /21
Percent correct
84 97/73
82 61/73
65 /59
56 /14
Table XIII
Effect on the color of a sample caused by substitution of a dark for a light background.
Hue
Number of sample-illuminant combinations
Observed to change in the RYGBR sense by more than 1/16 of the hue circuit
Observed to change by less than 1/16 of the hue circuit
Observed to change in the RBGYR sense by more than 1/16 of the hue circuit
Numbers preceded by the “less-than” (<) sign indicate spectral transmissions greater than those possessed by the respective filters.
Table VI
Trilinear coordinates (r,g) of the light reflected from each sample and the apparent reflectances (A) of the samples for each of the five illuminants used.
Abbot-Priest Sunlight
Red Illuminant
Yellow Illuminant
Green Illuminant
Blue Illuminant
Sample
r
g
A
r
g
A
r
g
A
r
g
A
r
g
A
MgO
0.458
0.458
1.000
0.958
0.042
1.000
0.705
0.295
1.000
0.372
0.613
1.000
0.237
0.351
1.000
R3/7
.606
.342
.087
.961
.039
.276
.792
.208
.151
.390
.597
.049
.243
.338
.048
R5/10
.628
.327
.221
.959
.041
.706
.796
.204
.404
.391
.595
.110
.241
.344
.110
R7/6
.527
.408
.459
.958
.042
.781
.744
.255
.618
.380
.606
.357
.240
.347
.346
YR4/5
.574
.394
.163
.959
.041
.297
.735
.265
.246
.401
.589
.110
.248
.365
.069
Y5/7
.525
.448
.241
.957
.043
.272
.700
.299
.288
.393
.598
.221
.254
.373
.097
Y7/8
.532
.449
.490
.958
.042
.577
.703
.296
.588
.393
.598
.455
.265
.398
.159
G3/4
.437
.490
.094
.961
.039
.072
.686
.313
.078
.367
.619
.107
.236
.369
.093
G5/7
.407
.539
.285
.953
.047
.087
.637
.362
.171
.362
.624
.377
.237
.413
.267
G7/7
.439
.497
.522
.956
.044
.329
.677
.322
.428
.367
.619
.596
.237
.384
.493
B3/5
.374
.485
.114
.958
.042
.064
.685
.314
.072
.351
.629
.133
.232
.353
.217
B5/6
.386
.491
.277
.959
.041
.161
.684
.315
.185
.354
.627
.324
.232
.363
.472
B7/4
.427
.478
.531
.957
.043
.381
.690
.309
.445
.365
.619
.581
.236
.356
.642
P3/6
.440
.423
.108
.962
.038
.153
.730
.270
.119
.370
.612
.097
.237
.325
.153
P5/6
.456
.434
.253
.961
.039
.359
.731
.269
.273
.370
.614
.235
.236
.337
.310
PB7/4
.428
.467
.458
.960
.040
.428
.704
.294
.405
.364
.619
.485
.236
.350
.600
Table VII
Constants used in computing the trilinear coordinates (rn,gn,bn) of the achromatic points for the five illuminants studied (Eq. 3).
This constant refers to the dark background (A0=0.10); the one given just above to the light background (A0=0.80).
Table IX
Computed hues, lightnesses and saturations for 3 hypothetical nonselective samples for both light and dark backgrounds, for the 5 illuminants, and for 4 observing situations (Cases 1 to 4).
Illuminant
A0
Sample
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Abbot-Priest sunlight
0.80
N 2/0
RB 0.2/0.2
RB 0.3/0.2
N /0.0
YR /1.1
N 5/0
RB 3.5/0.1
RB 5.3/0.1
N /0.0
YR /1.1
N 9/0
N 8.8/0.0
Y 9.4/0.1
N /0.0
YR /1.1
.10
N 2/0
RB 0.3/0.1
RB 0.6/0.1
N /0.0
YR /1.1
N 5/0
N 5.2/0.0
N 6.9/0.0
N /0.0
YR /1.1
N 9/0
YG 9.4/0.1
YG 9.7/0.1
N /0.0
YR /1.1
Red
.80
N 2/0
B 0.2/6.3
B 0.3/5.2
N /0.0
YR /33.9
N 5/0
RB 3.5/1.8
R 5.3/1.7
N /0.0
YR /33.9
N 9/0
YR 8.7/6.8
YR 9.4/5.8
N /0.0
YR /33.9
.10
N 2/0
B 0.3/4.3
B 0.6/2.3
N /0.0
YR /33.9
N 5/0
YR 5.0/4.6
YR 6.9/5.1
N /0.0
YR /33.9
N 9/0
YR 9.3/12.0
YR 9.7/7.8
N /0.0
YR /33.9
Yellow
.80
N 2/0
B 0.2/2.3
B 0.3/2.0
N /0.0
YR /16.5
N 5/0
RB 3.5/0.9
R 5.3/0.6
N /0.0
YR /16.5
N 9/0
Y 8.8/1.9
Y 9.4/1.6
N /0.0
YR /16.5
.10
N 2/0
RB 0.3/1.7
RB 0.6/1.1
N /0.0
YR /16.5
N 5/0
YR 5.1/1.3
Y 6.9/1.4
N /0.0
YR /16.5
N 9/0
Y 9.4/3.6
Y 9.7/2.2
N /0.0
YR /16.5
Green
.80
N 2/0
RB 0.2/1.3
RB 0.3/1.1
N /0.0
G /8.8
N 5/0
RB 3.5/0.5
RB 5.3/0.2
N /0.0
G /8.8
N 9/0
YG 8.8/0.7
YG 9.4/0.6
N /0.0
G /8.8
.10
N 2/0
RB 0.3/0.9
RB 0.6/0.6
N /0.0
G /8.8
N 5/0
YG 5.2/0.4
YG 6.9/0.4
N /0.0
G /8.8
N 9/0
YG 9.4/1.6
YG 9.7/0.9
N /0.0
G /8.8
Blue
.80
N 2/0
RB 0.2/2.5
RB 0.3/1.9
N /0.0
RB /20.0
N 5/0
RB 3.5/0.9
RB 5.3/0.9
N /0.0
RB /20.0
N 9/0
B 8.8/4.7
B 9.4/3.4
N /0.0
RB /20.0
.10
N 2/0
RB 0.3/1.0
RB 0.6/0.9
N /0.0
RB /20.0
N 5/0
B 5.2/1.7
B 6.9/1.7
N /0.0
RB /20.0
N 9/0
B 9.4/5.5
B 9.7/2.8
N /0.0
RB /20.0
Table X
Comparison of observed and computed color descriptions. (Hue, lightness and saturation (HL/S) of the 15 selective samples studied. Illuminant: Abbot-Priest sunlight taken as representative of south daylight.)
Sample
Average Observed ValuesHL/S
Individual Observer Range ΔHΔL/ΔS
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Light background (A0=0.80)
R 3/7
R 2.6/5.1
R 1–3/2–7
YR 1.6/9.6
YR 2.6/9.6
YR /9.5
YR /10.6
R 5/10
R 5.2/10
R 4–6/10
YR 4.0/10.9
YR 5.8/10.9
YR /10.9
YR /12.0
R 7/6
R 6.9/5.8
RB-YR 5–8/3–8
YR 6.8/4.4
YR 8.2/4.4
YR /4.4
YR /5.5
YR 4/5
YR 3.8/4.8
YR 3–5/1–7
YR 3.0/7.1
YR 4.7/7.1
YR /7.1
YR /8.3
Y 5/7
gY 4.6/4.4
Y-YG 4–5/2–6
Y 4.3/4.4
Y 6.1/4.4
Y /4.4
Y /5.4
Y 7/8
Y 6.7/9.4
Y 6–8/9–10
Y 7.1/4.9
Y 8.3/4.9
Y /5.0
Y /5.9
G 3/4
yG 2.0/2.9
YG-G 1–3/1–6
G 1.7/1.9
G 2.8/1.9
G /2.0
YG /1.3
G 5/7
G 5.3/9.8
G 4–6/9–10
G 4.9/5.0
G 6.7/5.0
G /5.0
G /4.2
G 7/7
yG 7.3/5.2
YG-G 7–8/4–8
G 7.4/2.4
G 8.5/2.4
G /2.4
YG /1.9
B 3/5
B 3.0/6.2
B 2–4/5–7
B 2.1/5.3
B 3.4/5.3
B /5.2
B /4.2
B 5/6
B 4.9/7.9
B 4–6/7–9
BG 4.8/4.4
BG 6.6/4.4
BG /4.4
B /3.3
B 7/4
gB 7.3/3.4
BG-B 7–8/1–8
BG 7.4/1.9
BG 8.6/1.9
BG /1.9
BG /0.8
P 3/6
RB 2.9/6.8
RB 2–4/6–8
RB 2.0/3.4
RB 3.3/3.4
RB /3.3
RB /3.3
P 5/6
RB 5.1/5.3
RB 5–6/4–8
RB 4.5/1.8
RB 6.3/1.8
RB /1.8
R /2.2
PB 7/4
B 6.8/3.6
rB-B 6–7/1–8
B 6.8/1.9
B 8.1/1.9
B /1.9
RB /1.0
Dark background (A0=0.10)
R 3/7
R 3.1/5.1
R 1–5/3–8
YR 2.7/9.6
YR 4.2/9.6
YR /9.5
YR /10.6
R 5/10
R 6.0/10
RB-R 5–7/10
YR 5.7/11.0
YR 7.3/10.9
YR /10.9
YR /12.0
R 7/6
R 7.4/6.8
RB-YR 7–9/3–9
YR 8.1/4.4
YR 8.9/4.4
YR /4.4
YR /5.5
YR 4/5
YR 4.1/5.9
YR 2–5/2–9
YR 4.7/7.1
YR 6.4/7.1
YR /7.1
YR /8.3
Y 5/7
Y 4.6/4.5
Y 2–6/2–6
Y 6.0/4.5
Y 7.5/4.4
Y /4.4
Y /5.4
Y 7/8
Y 7.4/9.9
Y 6–9/9–11
Y 8.3/4.9
Y 9.0/5.0
Y /5.0
Y /5.9
G 3/4
G 2.4/2.2
G 1–4/2–4
G 2.8/1.9
G 4.5/1.9
G /2.0
YG /1.3
G 5/7
G 5.7/9.0
G 4–8/8–10
G 6.6/5.0
G 7.9/5.0
G /5.0
G /4.2
G 7/7
G 7.4/4.7
YG-BG 6–9/3–8
G 8.5/2.4
G 9.2/2.4
G /2.4
YG /1.9
B 3/5
B 3.2/7.2
B 2–4/7–8
B 3.3/5.3
B 5.1/5.3
B /5.2
B /4.2
B 5/6
B 5.4/6.8
B 4–6/5–8
BG 6.4/4.3
BG 7.9/4.3
BG /4.4
B /3.3
B 7/4
gB 7.6/1.8
BG-B 5–10/1–4
BG 8.5/1.9
BG 9.2/1.9
BG /1.9
BG /0.8
P 3/6
RB 3.1/5.7
RB 2–4/4–9
RB 3.2/3.4
RB 4.9/3.4
RB /3.3
RB /3.3
P 5/6
RB 5.2/3.8
RB 4–6/1–7
RB 6.1/1.7
RB 7.6/1.7
RB /1.8
R /2.2
PB 7/4
rB 7.2/1.7
RB-B 5–8/1–3
B 8.6/1.9
B 8.9/1.8
B /1.9
RB /1.0
Table XI
Comparison of observed and computed color descriptions. Hue, lightness and saturation (HL/S) of the 15 selective samples studied under the 4 chromatic illuminants; see Table V.
Sample
Average Observed ValuesHL/S
Individual Observer Range ΔHΔL/ΔS
Computed for Different Viewing Situations
Momentary Fixation of Sample
Fixation of Sample for Several Seconds
Illuminant Color Discounted
Aperture Color for Daylight Adapted Eye
(Case 3)
(Case 4)
(Case 2)
(Case 1)
Red illuminant, light background (A0=0.80)
R 3/7
bR 4.0/1.2
RB-YR 3–5/0–4
R 4.7/1.7
YR 6.6/3.0
YR /0.2
YR /34.1
R 5/10
rYR 9.2/1.4
R-rY 8–10/0–4
YR 8.5/6.6
YR 9.3/5.9
YR /0.1
YR /33.9
R 7/6
YR 9.7/1.3
yR-rY 8–10/0–4
YR 9.0/7.0
YR 9.5/6.1
N /0.0
YR /33.9
YR 4/5
bR 4.2/1.1
RB-YR 3–5/0–4
R 5.0/1.9
YR 6.8/3.1
YR /0.1
YR /33.9
Y 5/7
bR 3.9/1.0
RB-YR 3–5/0–4
R 4.6/1.5
YR 6.5/2.7
BG /0.1
YR /33.8
Y 7/8
yR 7.5/1.0
R-YR 6–9/0–2
YR 7.7/5.3
YR 8.8/5.3
N /0.0
YR /33.9
G 3/4
B 1.1/1.9
BG-BR 0–2/0–6
B 1.1/4.9
B 2.1/3.3
YR /0.2
YR /34.1
G 5/7
B 1.4/1.9
BG-RB 1–2/0–6
B 1.5/4.8
B 2.5/3.0
BG /0.4
YR /33.6
G 7/7
yR 4.6/1.1
R-YR 4–6/0–4
R 5.4/2.0
YR 7.1/3.3
BG /0.1
YR /33.7
B 3/5
gB 1.1/1.8
BG-B 0–2/0–6
B 0.9/5.3
B 1.6/3.6
N /0.0
YR /33.9
B 5/6
RB 2.3/1.4
B-R 1–4/0–6
B 2.9/2.6
RB 4.6/1.5
YR /0.1
YR /33.9
B 7/4
yR 5.2/1.0
R-YR 4–6/0–4
YR 6.0/2.7
YR 7.6/3.8
BG /0.1
YR /33.8
P 3/6
RB 2.3/1.5
B-YR 1–4/0–6
B 2.7/2.7
RB 4.4/1.4
YR /0.3
YR /34.2
P 5/6
bR 5.0/1.0
RB-YR 4–6/0–4
YR 5.8/2.8
YR 7.4/3.9
YR /0.2
YR /34.1
PB 7/4
R 5.8/1.3
RB-YR 5–7/0–4
YR 6.5/3.6
YR 7.9/4.3
YR /0.1
YR /34.0
Red illuminant, dark background (A0=0.10)
R 3/7
YR 5.5/3.4
YR 5–6/2–5
YR 6.3/7.0
YR 7.8/6.3
YR /0.2
YR /34.1
R 5/10
YR 9.7/6.3
YR 7–11/3–12
YR 9.2/11.8
YR 9.6/7.8
YR /0.1
YR /33.9
R 7/6
YR 9.8/6.3
YR 7–11/3–12
YR 9.4/12.2
YR 9.8/7.8
N /0.0
YR /33.9
YR 4/5
YR 6.3/4.1
YR 5–7/3–6
YR 6.6/7.1
YR 8.0/6.1
YR /0.1
YR /33.9
Y 5/7
YR 6.0/3.4
YR 5–8/2–5
YR 6.2/6.5
YR 7.8/6.0
BG /0.1
YR /33.8
Y 7/8
YR 9.0/6.0
YR 7–10/3–11
YR 8.6/10.7
YR 9.3/7.5
N /0.0
YR /33.9
G 3/4
RB 1.3/0.4
RB-R 1–2/0–2
RB 1.9/1.9
R 3.5/2.0
YR /0.2
YR /34.1
G 5/7
R 1.8/0.6
RB-R 1–3/0–4
RB 2.4/1.5
YR 4.2/2.0
BG /0.4
YR /33.6
G 7/7
YR 6.7/3.9
YR 6–8/3–6
YR 6.9/7.6
YR 8.3/6.2
BG /0.1
YR /33.7
B 3/5
RB 1.0/0.6
B-RB 0–2/0–4
B 1.6/2.3
R 3.0/1.5
N /0.0
YR /33.9
B 5/6
YR 3.7/1.7
R-YG 3–4/1–4
YR 4.4/3.5
YR 6.3/4.4
YR /0.1
YR /33.9
B 7/4
YR 7.5/4.6
YR 6–8/3–8
YR 7.4/8.4
YR 8.6/6.7
BG /0.1
YR /33.8
P 3/6
rYR 3.8/2.0
R-YR 3–4/1–4
YR 4.2/3.5
YR 6.1/4.4
YR /0.3
YR /34.2
P 5/6
YR 6.9/4.2
YR 5–8/2–8
YR 7.2/8.4
YR 8.5/6.8
YR /0.2
YR /34.1
PB 7/4
YR 7.9/5.0
YR 6–9/3–10
YR 7.8/9.4
YR 8.8/7.2
YR /0.1
YR /34.0
Yellow illuminant, light background (A0=0.80)
R 3/7
rBR 3.8/10.0
RB-R 3–6/4–16
R 2.8/6.3
R 4.4/6.5
YR /6.2
YR /22.4
R 5/10
yR 6.8/9.7
R-YR 5–9/5–16
YR 6.3/7.3
YR 7.8/7.5
YR /6.4
YR /22.7
R 7/6
rYR 8.3/6.1
R-Y 8–10/3–10
YR 8.0/4.2
YR 9.0/4.1
R /2.8
YR /19.1
YR 4/5
bR 4.4/3.3
RB-Y 3–5/1–4
R 4.3/2.6
R 6.2/2.8
YR /2.1
YR /18.5
Y 5/7
YG 4.8/0.2
Y-G 4–6/0–1
RB 4.9/0.4
YR 6.7/0.5
BG /0.3
YR /16.3
Y 7/8
gY 8.3/0.4
Y-YG 8–10/0–1
Y 7.8/1.4
Y 8.8/1.4
BG /0.1
YR /16.4
G 3/4
bRB 1.5/4.2
B-RB 1–2/0–8
B 1.3/2.6
B 2.1/1.9
BG /1.3
YR /15.2
G 5/7
gBG 3.8/6.1
G-B 3–6/3–8
BG 3.1/4.8
BG 4.8/4.4
BG /4.8
YR /12.1
G 7/7
yG 6.4/4.3
YG-G 5–7/2–8
G 6.5/1.1
G 7.9/1.1
BG /1.9
YR /14.7
B 3/5
bRB 1.5/4.7
B-RB 1–2/0–10
B 1.2/2.6
B 1.9/2.1
BG /1.4
YR /15.2
B 5/6
gB 3.1/1.4
BG-RB 2–4/0–3
B 3.3/1.7
BG 5.1/1.0
BG /1.4
YR /15.1
B 7/4
yG 6.7/2.7
YG-G 5–7/1–4
YG 6.6/0.4
YG 8.0/0.5
BG /1.0
YR /15.5
P 3/6
rRB 2.5/5.5
RB-YR 2–3/2–10
RB 2.2/1.8
R 3.5/2.1
YR /1.8
YR /18.2
P 5/6
bR 4.7/3.3
RB-Y 4–6/1–4
R 4.7/2.3
YR 6.5/2.6
YR /1.8
YR /18.2
PB 7/4
YG 6.2/0.2
Y-G 5–7/0–1
YR 6.3/0.9
YR 7.8/1.1
RB /0.1
YR /16.5
Yellow illuminant, dark background (A0=0.10)
R 3/7
bR 4.9/8.4
RB-R 4–6/7–12
YR 4.2/7.0
YR 6.1/7.2
YR /6.2
YR /22.4
R 5/10
rYR 7.7/10.4
R-YR 6–10/8–16
YR 7.6/8.5
YR 8.7/8.0
YR /6.4
YR /22.7
R 7/6
yYR 8.6/8.9
R-Y 7–10/6–16
YR 8.9/5.6
YR 9.4/4.6
R /2.8
YR /19.1
YR 4/5
YR 5.3/5.2
YR 3–6/4–7
YR 5.9/3.6
YR 7.6/3.5
YR /2.1
YR /18.5
Y 5/7
gY 5.8/3.5
Y-YG 5–6/1–6
Y 6.5/1.8
Y 8.0/3.6
BG /0.3
YR /16.3
Y 7/8
gY 8.4/6.6
Y-yYG 7–10/2–14
Y 8.8/3.1
Y 9.4/2.0
BG /0.1
YR /16.4
G 3/4
yG 1.5/0.6
YG-G 1–2/0–2
B 2.2/1.4
BG 3.6/0.7
BG /1.3
YR /15.2
G 5/7
G 4.7/8.6
G 4–6/7–12
G 4.7/3.8
G 6.5/3.7
BG /4.8
YR /12.1
G 7/7
gYG 7.2/6.6
YG-G 6–8/4–10
YG 7.8/1.9
YG 8.8/1.4
BG /1.9
YR /14.7
B 3/5
yG 1.4/0.4
YG-G 1–2/0–2
B 2.0/1.4
BG 3.4/0.9
BG /1.4
YR /15.2
B 5/6
gYG 4.2/4.3
YG-G 3–5/3–6
YG 5.0/0.7
YG 6.8/0.7
BG /1.4
YR /15.1
B 7/4
YG 7.2/5.3
Y-G 6–8/2–8
Y 7.9/2.2
Y 8.9/1.4
BG /1.0
YR /15.5
P 3/6
rYR 3.1/3.4
R-YR 2–5/2–6
R 3.4/2.4
YR 5.2/2.6
YR /1.8
YR /18.2
P 5/6
YR 5.3/4.9
YR 4–6/3–6
YR 6.3/3.6
YR 7.8/3.3
YR /1.8
YR /18.2
PB 7/4
Y 7.0/4.7
Y-gY 6–8/2–8
Y 7.6/2.6
Y 8.7/1.9
RB /0.1
YR /16.5
Green illuminant, light background (A0=0.80)
R 3/7
RB 1.0/3.3
RB 1–2/0–8
R 0.5/2.1
R 1.0/1.8
YR /1.2
G /7.8
R 5/10
R 2.3/2.4
RB-yG 2–3/0–6
R 2.0/1.9
R 3.2/1.7
YR /1.3
G /7.7
R 7/6
rY 5.5/1.4
R-G 4–7/0–4
YR 5.8/0.5
YR 7.4/0.5
YR /0.5
G /8.4
YR 4/5
YR 2.5/2.8
R-YG 2–3/0–6
R 2.0/2.4
R 3.2/2.2
YR /1.9
YG /7.4
Y 5/7
gY 4.1/2.8
YR-YG 3–5/1–4
YR 4.0/1.5
YR 5.8/1.3
YR /1.3
YG /7.9
Y 7/8
gY 7.1/5.1
Y-YG 6–8/3–8
YR 6.7/1.3
YR 8.1/1.3
YR /1.3
YG /7.9
G 3/4
B 2.3/1.8
G-RB 2–3/0–6
RB 2.0/0.7
RB 3.2/0.4
G /0.4
G /9.1
G 5/7
G 5.8/2.4
G 4–8/0–4
G 6.0/0.8
G 7.6/0.9
G /0.7
G /9.4
G 7/7
G 8.3/0.9
G 7–9/0–2
G 7.9/0.8
G 8.9/0.9
G /0.4
G /9.1
B 3/5
B 2.8/3.8
B 2–4/2–6
B 2.4/1.3
BG 3.9/1.3
BG /1.3
G /9.8
B 5/6
B 5.1/3.9
B 3–6/1–7
BG 5.4/1.1
BG7.1/1.2
BG /1.2
G /9.6
B 7/4
B 8.0/0.5
BG-B 6–9/0–2
G 7.8/0.8
G 8.8/0.9
BG /0.5
G /9.1
P 3/6
bRB 2.3/2.1
B-RB 2–3/0–6
RB 1.7/1.1
RB 2.8/0.8
B-RB /0.2
G /8.7
P 5/6
B 4.1/0.8
BG-RB 2–5/0–4
RB 4.2/0.4
B 6.1/0.1
BG /0.1
G /8.8
PB 7/4
B 7.2/1.0
B 6–8/0–2
G 7.0/0.7
G 8.3/0.7
BG /0.5
G /9.1
Green illuminant, dark background (A0=0.10)
R 3/7
bR 1.0/2.2
RB-R 0–2/0–6
R 1.0/1.7
R 1.9/1.4
YR /1.2
G /7.8
R 5/10
yYR 2.9/2.4
YR-Y 2–6/1–4
YR 3.2/1.4
YR 4.9/1.3
YR /1.3
G /7.7
R 7/6
gY 7.7/3.6
Y-YG 6–10/1–10
YG 7.2/0.9
Y 8.4/0.8
YR /0.5
G /8.4
YR 4/5
yYR 3.6/3.8
YR-Y 3–6/2–6
YR 3.2/2.0
YR 4.9/1.9
YR /1.9
YG /7.4
Y 5/7
gY 6.1/4.8
Y-YG 4–8/2–10
Y 5.6/1.4
Y 7.3/1.3
YR /1.3
YG /7.9
Y 7/8
Y 8.5/6.7
Y 8–12/3–16
Y 8.0/1.6
Y 8.9/1.4
YR /1.3
YG /7.9
G 3/4
G 2.8/1.2
G 2–4/0–4
BG 3.2/0.3
G 4.8/0.4
G /0.4
G /9.1
G 5/7
yG 7.7/4.4
YG-G 7–10/2–10
G 7.4/1.6
G 8.6/1.3
G /0.7
G /9.4
G 7/7
gYG 9.3/4.6
YG-G 9–12/1–12
YG 8.8/1.7
YG 9.4/1.2
G /0.4
G /9.1
B 3/5
gB 3.7/3.2
BG-B 3–4/2–6
BG 3.8/1.3
BG 5.6/1.4
BG /1.3
G /9.8
B 5/6
gB 7.2/4.0
G-B 6–10/2–10
G 7.0/1.7
G 8.2/1.5
BG /1.2
G /9.6
B 7/4
yG 9.2/4.2
YG-G 8–12/1–12
YG 8.7/1.6
YG 9.4/1.2
BG /0.5
G /9.1
P 3/6
RB 2.4/0.5
RB 1–4/0–4
RB 2.8/0.4
B-RB 4.6/0.2
B-RB /0.2
G /8.7
P 5/6
bG 5.9/2.0
G-BG 4–8/0–6
YG 5.7/0.6
YG 7.5/0.6
BG /0.1
G /8.8
PB 7/4
G 8.7/6.1
YG-BG 8–12/2–12
YG 8.2/1.5
G 9.0/1.0
BG /0.5
G /9.1
Blue illuminant, light background (A0=0.80)
R 3/7
rRB 1.4/1.8
RB-R 1–2/0–6
RB 0.5/2.7
RB 1.0/2.1
R /0.8
RB /20.3
R 5/10
bR 3.0/3.6
RB-R 3/2-6
RB 2.0/1.6
RB 3.3/1.3
R /0.4
RB /20.1
R 7/6
RB 5.9/3.1
RB-rRB 5–7/1–5
RB 5.7/1.3
RB 7.3/1.8
R /0.3
RB /20.0
YR 4/5
R 2.4/2.5
RB-YR 2–3/1–4
RB 1.1/0.2
Y 1.8/0.6
YG /1.5
RB /18.5
Y 5/7
rYR 3.5/2.8
RB-Y 3–4/1–4
YG 1.7/1.0
YG 2.9/1.6
YG /2.4
RB /17.6
Y 7/8
yYR 5.4/4.6
R-Y 4–6/1–6
YG 2.9/3.8
YG 4.6/3.9
YG /4.6
B /15.6
G 3/4
bRB 2.2/0.5
B-RB 2-3/0-2
B 1.6/0.5
YG 2.8/0.3
YG /1.2
B /19.0
G 5/7
yG 5.1/3.8
YG-BG 4–6/2–5
YG 4.7/3.5
YG 6.5/3.4
YG /4.4
B /16.7
G 7/7
yG 7.6/1.5
Y-G 6–9/0–4
BG 7.1/1.9
BG 8.4/2.1
YG /2.3
B /18.2
B 3/5
B 3.8/2.2
B 3–4/0–4
RB 3.9/0.9
RB 5.7/1.2
B /0.3
RB /20.2
B 5/6
gB 6.2/4.4
BG-B 5–7/2–6
B 6.9/2.1
B 8.2/2.3
G /0.7
RB /19.6
B 7/4
B 8.3/2.2
G-B 7–9/1–4
B 8.2/3.5
B 9.1/3.1
YG /0.3
RB /19.7
P 3/6
rB 3.0/3.4
B-RB 2–4/0–4
RB 2.8/2.8
RB 4.4/2.6
RB /1.8
RB /21.4
P 5/6
rB 4.8/2.8
B-rRB 4–5/0–5
RB 5.3/2.0
RB 6.9/2.5
RB /1.0
RB /20.8
PB 7/4
B 7.9/2.3
B 6–9/1–4
B 7.9/3.5
B 8.9/3.1
RB /0.1
RB /20.1
Blue illuminant, dark background (A0=0.10)
R 3/7
bR 1.2/2.0
RB-R 0–2/0–4
RB 1.0/1.7
RB 1.8/1.6
R /0.8
RB /20.3
R 5/10
rRB 3.3/4.2
RB-R 2–4/1–6
RB 3.2/1.3
RB 4.9/1.4
R /0.4
RB /20.1
R 7/6
rRB 7.2/2.5
RB-R 6–8/0–4
B 7.2/3.1
B 8.4/2.3
R /0.3
RB /20.0
YR 4/5
YR 2.7/3.3
rYR-YR 2–4/2–5
Y 2.0/1.0
Y 3.3/0.8
YG /1.5
RB /18.5
Y 5/7
yYR 3.9/4.2
YR-Y 3–5/3–5
YG 2.9/1.7
YG 4.6/1.5
YG /2.4
RB /17.6
Y 7/8
rY 6.2/6.2
YR-Y 5–7/4–8
YG 4.5/3.4
YG 6.2/3.3
YG /4.6
B /15.6
G 3/4
yG 2.7/1.7
YG-G 2–4/1–3
YG 2.8/0.4
G 4.4/0.5
YG /1.2
B /19.0
G 5/7
yG 6.4/5.1
YG-G 6–7/4–8
G 6.3/3.4
G 7.8/3.4
YG /4.4
B /16.7
G 7/7
gBG 8.3/2.1
G-B 8–9/1–8
BG 8.3/3.7
BG 9.1/2.2
YG /2.3
B /18.2
B 3/5
B 5.1/5.1
gB-B 4–6/4–8
B 5.6/2.2
B 7.2/2.0
B /0.3
RB /20.2
B 5/6
B 7.3/5.5
B 7–8/4–10
B 8.2/4.1
B 9.0/2.4
G /0.7
RB /19.6
B 7/4
B 9.0/3.4
B 8–10/1–10
B 9.0/5.1
B 9.5/2.6
YG /0.3
RB /19.7
P 3/6
bRB 4.1/4.2
B-RB 3–5/2–8
RB 4.3/2.9
RB 6.1/3.1
RB /1.8
RB /21.4
P 5/6
rB 6.3/4.4
B-RB 6–7/3–8
B 6.8/3.7
RB 8.1/2.9
RB /1.0
RB /20.8
PB 7/4
B 8.7/3.9
B 8–10/2–10
B 8.9/5.2
B 9.4/2.8
RB /0.1
RB /20.1
Table XII
Number of sample-illuminant-background combinations correct.
Illuminant
Apparent Reflectance of BackgroundA0
Number Correct
Case 3
Case 4
Case 2
Case 1
South
0.80
12 15/7
12 10/7
12 /7
11 /5
daylight
.10
12 14/7
12 8/7
12 /7
11 /6
Red
.80
15 15/12
15 7/12
15 /15
11 /0
.10
15 15/11
14 7/13
9 /3
12 /0
Yellow
.80
14 15/13
14 9/14
10 /15
5 /0
.10
12 15/12
12 6/10
5 /3
5 /0
Green
.80
10 15/13
9 12/13
10 /13
7 /2
.10
14 15/12
14 12/10
10 /8
8 /8
Blue
.80
11 11/14
10 12/14
7 /10
8 /0
.10
11 15/9
11 9/9
8/8
6/0
Total
.80
62 71/59
60 50/60
54 /60
42 /7
.10
64 74/51
63 42/49
44 /29
42 /14
Grand total correct
126 145/110
123 92/109
98 /89
84 /21
Percent correct
84 97/73
82 61/73
65 /59
56 /14
Table XIII
Effect on the color of a sample caused by substitution of a dark for a light background.
Hue
Number of sample-illuminant combinations
Observed to change in the RYGBR sense by more than 1/16 of the hue circuit
Observed to change by less than 1/16 of the hue circuit
Observed to change in the RBGYR sense by more than 1/16 of the hue circuit