34
Manual TECHKON SpectroDens
For the display of
dot area
(or dot percent-
age) in %, two measurements have to be
made: First the solid density patch and then
the %-patch, which is in this example a 80 %-
patch. The resulting dot percentage is in this
case 91.9 %; the referring
dot gain
is 11.9 %:
91.9 % - 80 % = 11.9 %
Should a solid density value be displayed
instead of the desired dot percentage value,
then the density measured first was signifi-
cantly higher than the second one. In this
case we recommend to delete the displayed
value by pressing the red escape button and
to measure again.
When making a measurement on a
gray
balance
patch, the referring density values
for all four process colors are shown in a bar
graph. The values for Cyan, Magenta and Yel-
low should be in close range to each other to
ensure a neutral gray balance without a color
hue.
It is important that the gray balance patch, on
which the measurement is taken, comprises
the right %-values to achieve a neutral gray
when printed correctly. The process standard
ISO 12647 for offset print defines the values as:
C = 50 %,
M = 40 % and
Y = 40 %.
The value for Black indicates how dark the
gray color is. The higher the value for Black
(= K) the darker the sample.
1. Measurement 2. Measurement
A gray balance patch is composed of different
portions of Cyan, Magenta and Yellow. It does
not include black ink.
K
C
M
Y
SLUR C+M K
C
M
Y
1
80% 40% BAL
2
K
C
M
Y
80% 40% 0
K
C
M
Y
K
C
M
Y
80% 40%
0
K
C
BAL
BAL
C+M
BAL
BAL
M
Y
S/D
