Above is a picture taken from bush, which leafs are turned from green to yellow. The spectrum measured from a yellow leaf can be seen below.

Color coordinates calculated from the spectrum
Spectrum Yellow
x 0.4644
y 0.4728
z 0.0628
X 52.1253
Y 53.0736
Z 7.0491
R 72.3752
G 49.4699
B 6.6207
L* 77.9184
a* 4.5997
b* 81.5783
u' 0.2398
v' 0.5494
u* 42.6918
v* 81.9887

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