Operator`s manual

INSTRUMENT FUNCTIONS
5-23
Dot Function (508, 518, 520, 528, 530 only)
Dot is calculated using either the Murray-Davies formula
or the Yule-Nielson formula. Murray-Davies simply
calculates dot by comparing the density of the tint minus
paper with the density of the solid minus paper. Your
instrument defaults to the Murray-Davies formula for
measurements.
The Yule-Nielson formula is similar to Murray-Davies
except that it allows you to compensate for the amount of
light that is absorbed or “trapped” when a dot
measurement is taken. This is done by first dividing the
densities of the paper and the solid by an “n” factor.
Using the Murray-Davies equation, your instrument “n”
factor is simply 1.00, so the paper and solid densities are
not affected. Using Yule-Nielson, the paper and solid
densities are divided by an “n” factor value that is based
on the properties of the substrate material. Yule-Nielson
formula is activated when the "n-factor" is turned on (see
Setting Options).
The Murray-Davies formula for calculating Dot is:
Apparent Dot Area =
()
()
110
110
100
-
-
-
-
D
D
t
s
x
Where: D
t
= Density of tint minus density of paper
D
s
= Density of solid minus density of paper
The Yule-Nielson formula for calculating Dot is:
Apparent Dot Area =
()
()
110
110
100
-
-
x
-D /n
-D /n
t
s
Where: D
t
= Density of tint minus density of paper
D
s
= Density of solid minus density of paper
n = “n” Factor