User guide

X-Rite eXact™ Instrument
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Metamerism Function Setting
Tap the Metamerism button and set the illuminant/observer combinations for metamerism
function measurements. By determining the metamerism index you define the mutual color
modification of two colors when the illuminant changes. You can set a maximum of three test
illuminants.
- Tap the observer icon to alternate between 2° and 10°.
- Swipe the illuminant wheel up or down to select the desired illuminant.
- Set the illuminant to “off” if all three are not required.
Metamerism Measurement
A metamerism measurement displays the index values for up to three illuminant/observer
combinations.
NOTE: The illuminant and observer parameters for metamerism have to be set before using this
function.
1. Select the metamerism function.
2. Measure or select a standard.
3. Measure the sample.
4. View measurement results.
Absolute Color Strength Function
The absolute color strength “K/S” is a measure for the concentration of a color.
Color Strength Function Setting
Tap the Color Strength button and set the calculation method and colorant.
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.
Absolute Color Strength Measurement
The absolute color strength function calculates the color strength of the measured sample.
Strength is calculated using the method selected in the function settings.
1. Select Absolute Color Strength.
2. Measure paper if required.
3. Measure the sample.
4. View data.
Simulated color of standard
Function, illum/obs, and
Measurement Condition
selected
Simulated color of sample
Illuminant/observer
combination selected
Metamerism index
values