X - R i t e e X a c t ™ I n s t r u m e n t
38
CIE XYZ
These tristimulus values of a color are the amounts of three primary colors in a three-component
additive model needed to match that test color. CIE XYZ serves as the basis from which many
other color spaces are defined. Shows delta XYZ values if a valid standard is present.
CIE Yxy
This function is directly derived from XYZ values. Y still represents luminance or brightness of a
color. The x and y are calculated from the XYZ values to define chromaticity of a color represent
normalized values of X and Z. A plot of x and y values for solid and overprint patches can reveal
the color gamut that can be achieved. The x and y values are also used as part of other functions
for estimating appearances of inks at varying thickness/concentrations. Delta Yxy values are also
shown if a valid standard is present.
Colormetric Measurement
Displays colorimetric measurement data for the selected function.
1.
Select L*a*b*, L*C*h°, XYZ, or Yxy colorimetric function.
2.
Measure sample.
3.
View data.
Paper Indices Function
This function can report data for Yellowness, Whiteness, and CIE Tint. Depending on the
function settings, 1 to 4 lines of data can be shown. Up to 4 of the following formulas can be
chosen for displaying in this function. Whiteness (E313-98, Berger, Stensby), Yellowness
(E313-98, D1925), CIE Tint, and Brightness. Difference values will show up on the right half of
the display when a valid standard is present.
Paper Indices Function Setting
Tap the Paper Indices button and select the paper indices that appear after a measurement. Up to
four indices can be selected for the function. Refer below for available options.
•
Yellowness E313 and Yellowness 1925:
used to evaluate white and near-white samples.
These samples yield numbers which correlate with visual rating of yellowness.
•
Whiteness E313, Whiteness Berger and Whiteness Stensby:
used to evaluate white and
near-white samples. These samples yield numbers which correlate with visual rating of
whiteness.
•
CIE Tint:
whiteness and tint play a similar role to a* and b* for white papers. Negative values
of tint correspond to reddish shades. Positive values of tint correspond to greenish shades.
•
Brightness
used to determine a blue reflectance of white, near-white, and naturally colored
pulp, paper, and paperboard.
Color values
Simulated color and timestamp of
reading displayed
Function, illum/obs, and
Measurement Condition selected
