Canon VarioPrint MICR i Series, Operation Manual

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L
∆E
[498] Difference between two colors in CIELAB
The following Delta E range illustrates how the values of Delta E may be interpreted for a specific
color evaluation.
• Delta E smaller than 1 is not visible by the human eye.
• Delta E between 1 and 2 is visible through close observation.
• Delta E between 2 and 10 is visible at a glance.
The printer uses two variants of Delta E:
• Delta E 2000,
△
E00, the industry standard.
• Delta E 1976,
△
E76, based on a less complicated and accurate distance calculation.
△
H (Delta H)
To indicate more color difference information than the total color difference Delta E, the hue error
△
H (Delta H) is used.
You can imagine Delta H as which color difference is left over when the lightness and the chroma
differences are ignored.
△ L (Delta L)
△
L (Delta L) is the lightness difference between the two colors. |ΔL| is the absolute value of
△
L
(Delta L).
The weighted |∆L| puts more emphasis on the color differences for light grays, where the K value
is lower than 50%. The goal of weighting is to reduce the importance of the lightness factor for
very dark grays. The human eye usually does not identify errors in the very dark gray color area.
This weighting definition is in accordance with the IDEAlliance G7 specification.
Learn about color differences
414 Chapter 12 - Print what you expect
VarioPrint i-series MICR