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CIE 2000 ΔE00
ΔE_00=[((∆L^')/(K_(L ) S_L ))^2+ ((∆C^')/(K_(C ) S_C ))^2+((∆H^')/(K_(H
) S_H ))^2+R_T ((∆C^')/(K_(C ) S_C ))((∆H^')/(K_(H ) S_H ))]1/2
L' =L*
a' =a*(1+G)
b' =b*
CIE 2000 ΔE00
∆E*_94=
))^2+((∆H*_ab)/(K_(H ) S_H ))^2 ]1/2
S_(L )=1
S_(C )=1+0.045 C*_ab
S_(H )=1+0.015 C*_ab
15.3
Colour offset assessment
-
Al+ stands for whitish, Al- for blackish
-
Aa+ stands for reddish, Aa- for greenish
-
Al+ stands for yellowish, Al for bluish
15.4
Colour difference perception
The colour difference unit of the NBS is derived from the unit of the colour difference
calculation formula established by Judd-Hunter. The colour difference of a colour is
referred to as the "NBS colour difference unit" if the absolute value is 1. The new colour
difference formulas developed later have often deliberately adapted the units so that
they come close to the NBS units. For example, the units of colour difference formulas
such as Hunter Lab and CIE LAB, CIE LUV are almost the same as the NBS units (not
the same). Therefore, do not misunderstand that the colour difference units calculated
by other colour difference formulas are all NBS units.
JCS-BA-e-2410
G=0.5(1- √((C ̅ * 7_ab)/(C ̅ * 7_ab+25^7 )))
[((∆L^')/(K_(L
)
S_L
))^2+
((∆C*_ab)/(K_(C
)
S_C
en | 35
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