X - R i t e e X a c t 2
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Color and Density Functions
The following is a description of each function.
Absolute Color Strength
The absolute color strength “K/S” is a measure for the concentration of a color.
To determine the color strength you must first choose one of the available calculation methods: Max K/S: K/S is
calculated at Point of minimum reflectance in the spectral curve.
Mean xyz: Calculates color strength by average mean xyz values across the visible spectrum. Next, select the
type of ink that is used to determine the color strength. You can choose Transparent ink, Opaque ink or Textile
dye.
All Densities
Used to display the density values for the measured sample for all filters (Cyan, Magenta, Yellow and Black).
This function can be configured to show additionally the density value at the wavelength of maximum density for
the spectral curve.
BestMatch
This function indicates if you can get a closer match (in
∆
E) to a standard color by adjusting the ink thickness
(offset printing) or concentration (flexo and gravure printing) on-press.
The illustration below shows the BestMatch function with the aid of the CIELAB color space using an example of
two different shades of green.
Color axis: Colorimetric axis to adjust color by ink thickness.
BestMatch point: Best possible color (e.g. green) that can be achieved by adjusting ink thickness or
concentration.
Brightener Index
This function is used to determine the amount of optical brightener (OBA) in the substrate according to ISO
15397. The value represents the difference between the CIE-b* values of the M1 and M2 measurement
condition.
CIE L*a*b*
This function is derived from the CIE 1931 XYZ color space in an effort to be perceptually uniform. The L*
dimension related to Lightness while a*(red/green) and b* (yellow/blue) are for color. Perceptually uniform
means that a change of the same amount in a color value should produce a change of about the same visual
importance. When a valid standard is present, the delta values will be included along with the
∆
E type that is
configured.
Summary of Contents for X-Rite eXact 2
Page 1: ...User Guide ...
Page 2: ......
