HunterLab EasyMatch QC, Руководство пользователя

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EasyMatch QC User’s Manual Version 2.1
A-18 Measurement Values
Z is the Z tristimulus value for the sample calculated for C/2° conditions.
For values greater than 8, 8 is displayed. For values less than 0, 0 is displayed.
When the D1500 function is optimized, the following equation is used:
D1500* =
α
+
β
(DX + DY + DZ)
where
DX, DY, DZ, X, Y, and Z are as described above
α
is the intercept correction constant entered by the user
β
is the slope correction constant entered by the user.
To obtain the D1500 value for a specimen, complete the steps below.
1. Standardize the instrument in a transmission mode using clear liquid in a 33-mm transmission cell
for setting the top of scale.
2. Select ASTM D1500-33 mm and ASTM D1500 Dilution Factor as indices for display in the Color
Data Table.
3. Two columns will be added to the color data table, one for the index and another for the dilution
factor.
4. To edit the scale constants, choose Adjust Scale Factors from the Options menu and then ASTM
D1500-33mm from the submenu. Click OK, edit the constants, and indicate the dilution factor as
desired.
5. Measure the sample desired in a 33-mm transmission cell. The ASTM D1500-33 mm value will be
displayed in that column and the dilution factor will be displayed in the ASTM D1500 Dilution
Factor column.
When ASTM D1500 data is recalled, the dilution factor will be correctly displayed and the index value
will be recalculated based on the current constants.
ASTM D1500 Difference is also available, and is defined as follows:
dASTM D1500-33 mm = (ASTM D1500-33 mm)
sample
- (ASTM D1500-33 mm)
standard.
b/a Ratio
b/a Ratio is simply the b of Hunter L, a, b divided by the a of Hunter L, a, b.
b/a Difference is also available, and is defined as follows:
db/a = (b/a)
sample
- (b/a)
standard.