HunterLab EasyMatch QC, Руководство пользователя

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EasyMatch QC User’s Manual Version 2.1
A-10 Measurement Values
2
1
H L c
T
2
H
2
C
2
L
S K
2000 * dH
S KC
2000 * dC
R
S KH
2000 * dH
+
S KC
2000 * dC
+
S KL
2000 * dL
2000 * dE




















+


















=
where:
dL* 2000, dC* 2000, and dH* 2000 are as described earlier in this chapter (as dL*, dC*, and
dH*)
KL:KC:KH ratio. This ratio is generally 1:1:1 for coatings, 1.3:1:1 for plastics, and 2:1:1 for
textiles.
SL = 1
SC = 1 + 0.045 C*
ab
SH = 1 + 0.015 C*
ab
R
T
= Rotation function = -sin(2
∆Θ
)R
C
∆Θ
= 30 exp
















2
25
275 - h
-
2
1
7
7
7
C
25 00 * C
00 * C
2 R








+
=
.
FMC-2 (Friele - MacAdam - Chickering) Color Difference
Red-green (dRedGrn FMCII) differences, yellow-blue (dYelBlu FMCII) differences, total lightness
differences (dL FMCII), and total color differences (dE FMCII) between standard and sample are
computed according to the Friele-MacAdam-Chickering metric (
JOSA , February 1968, p. 292 and
August 1969, p. 986).
The FMC-2 unit of color difference is based on just noticeable, or threshold, color difference data
published in 1942. Friele used the data in his suggested color-difference formula, which was modified
later by MacAdam, and then by Chickering. The FMC-2 Scale is a color difference scale only and was
designed for Illuminant C and 2° standard observer conditions only. It has been successfully used for
non-saturated colors under illuminants D65 and A as well as 10° standard observer conditions.
ISO Grey Scale
ISO Grey Scale indicates the amount of fading or color alteration that occurs with environmental
exposure or washing of textiles. The loss of color using the ISO Grey Scale is evaluated by comparison
to five pairs of gray standards similar to those shown below. One half of each standard is always of
identical chroma to the starting specimen. The second half ranges from the starting chroma (no loss of
color) to white (loss of all color). The amount of contrast between the treated and untreated fabric is