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CHAPTER 2
– Measurement functions
SCTV
The
Spot Colour Tone Value (SCTV)
function, which is defined in ISO 20654:2017, pro-
vides a precise colorimetric quality inspection for spot colors. SpectroDens supports
SCTV for single tone value measurements and the SCTV printing curve (see page 42).
1. First place the measurement head above
a solid patch and start the measurement by
pressing the green button. The solid density
value will be displayed.
2. Now make a second measurement on a
%-patch and the
dot area
in % will be shown.
In this case a measurement has been taken on
a 80 %-patch.
The resulting dot gain can be easily calculated:
81.2 % - 80 % = 1.2 %
The dot gain value gives the information
to what degree a point is enlarged (or de-
creased) during each process step of the re-
production process chain.
The double arrow on the left side of the de-
vice display indicates which measurement
has to be done next.
Should several dot area values refer to the
same solid density, this value has to be mea-
sured only once and can be saved for con-
secutive %-measurements. After a solid den-
sity measurement, just keep the enter button
pushed for approximately 3 seconds until the
density value is framed. Now an unlimited
number of %-measurements can be made.
Deactivating is done by keeping the enter
button pressed again.
1. 2.
80% 40%
S2
S1
0
BAL
S2
S1
80% 40%
K
C
M
Y
S2
S1
K
K
C
M
Y
K
C
M
Y
