HunterLab EasyMatch QC, User Manual

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EasyMatch QC User’s Manual Version 2.1
A-8 Measurement Values
SH = (FT + 1 - F) SC
2 2
* b * a * C
+ =
h = arctan
b *
a *
°




dL* = L*
SMP
- L*
STD
dC* = C*
SMP
- C*
STD
2 2 2
* dC * dL * dE = * dH
− −
1900 * C
* C
F
4
4
+
=
T = 0.36 + |0.4 cos (35 + h)| if h = 164° or h > 345°
T = 0.56 + |0.2 cos (168 + h)| if 164° < h < 345°
Tolerances are: dL* = (cf) lSL dL* CMC = cf
dC* = (cf) cSC dC* CMC = cf
dH* = (cf) SH dH* CMC = cf
dE CMC = cf
For a more detailed description of CMC, refer to Calculation of Small Color Differences for
Acceptability , AATCC Test Method 173-1992 published in the AATCC Technical Manual.
CIE TC 1-29
CIE TC 1-29, also called the CIE 1994 (dL CIE94 dC CIE94 dH CIE94) color difference scale, is a test
scale that may eventually be approved as an official CIE scale.
dE CIE94 is the total color difference.
2
1
2
H H
2
C C
2
L L
v
S K
CIE94 dH
+
S K
CIE94 dC
+
S K
CIE94 dL
* K CIE94 dE


























=
where:
dL CIE94, dC CIE94, and dH CIE94 are as described earlier in this section (as dL*, dC*, and
dH*)
SL = 1
SC = 1 + 0.045 C*
SH = 1 + 0.015 C*.