X-Rite 939, Operator'S Manual

Page: 93 / 108

C H A P T E R F I V E
5-36
Hue/Grayness
The instrument can report hue error, grayness, and saturation
with or without paper subtracted. Hue/Gray measures the
selected ink through all three filters (cyan, magenta, and yellow).
Paper mode is selected from the Density Options menu, located
in the Configuration menu
(refer to Section Four).
Hue error, grayness, and saturation are calculated using the
following formulas.
100
x
D D
D D
H
L H
L M
−
−
=
100
x
D
D
G
H
L =
L H
D D S
− =
Where: D
H
= Highest density of C, M, or Y.
D
M
= 2nd highest density of C, M, or Y.
D
L
= Lowest density of C, M, or Y.
To access the Hue/Grayness function:
1.
Use the Tab keys
$@
to highlight
Hue/Grayness
.
–
M A I N M E N U
–
↑
D e n s i t y
D o t / T o n e
T r a p
H u e / G r a y n e s s
↓
X — R i t e
9 3 9
— — — — — —
X X X X
* * * * * *
2.
Press the Enter key
#
to access the Hue/Grayness function.
Measuring Paper
When you select hue/grayness minus paper from the
Configuration menu, you must provide a reading of the paper
before taking measurements. The instrument takes the density
value of the paper and automatically subtracts it from
subsequent measurements.
To measure paper:
1.
If not selected, press the Tab keys
$@
to highlight Paper.
<
Measure Paper
> appears in the user dialog. The paper
values displayed are the current values set in the
instrument.
H u e / G r a y T
<
M e a s u r e P a p e r
>
Paper
Hue/Gray
V 0.114
C 0.116
M 0.113
Y 0.123