Techkon SpectroDens Manual page 60

The ∆E*-value is calculated as long as the
difference is in a reasonable range.
If the difference exceeds a limit, then only the
measured density value is displayed without
comparison.
This procedure works for all CMYK colors.
The selected paper type and backing type are
always indicated.
The color detection works for trapping
patches as well. The recognized type of patch
is displayed in the printing order of the two
colors.
The measured value is compared with the
ISO reference and the difference is displayed
as ∆E*.
If paper white or any other undefined
patch is measured then all four densities are
displayed simultaneously.
Page 60 Manual TECHKON SpectroDens Chapter 2 – Measurement functions