As of EasyMatch QC ver 4.86 BG036 Display of dEf with ISO Grey Scale in Color Data View - dEf is a component calculated as part of the ISO Grey Scale calculation.
Under OPTIONS > ADJUST SCALE FACTORS, there would be an ISO Grey Scale metric in which a checkable box (default unchecked) would be displayed. The label beside the box would be “dEf Total Difference”.
If the dEf box is checked and the ISO Grey Scale difference metric is selected in COLOR DATA VIEW > CONFIGURE, a column listing the dEf value would be displayed for samples only (standard would be blank) to the right of the ISO Grey Scale difference.
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