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CHAPTER 2
– Measurement functions
Dot Area
For the function
Dot Area
(= dot percentage) two measurements have to be carried
out. First a measurement on a solid patch and then a measurement on a %-patch
(= screen patch). The dot area value is calculated with the Murray-Davies formula.
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 40 %-patch.
The resulting dot gain can be easily calculated:
59 % - 40 % = 19 %
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.
K
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SLUR C+M K
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1
80% 40% BAL
2
1.
2.
