Computer Products of America Image Scanner Operator's Guide fi-4990C

4-8
Drop-out Color
A drop-out color is a color visible by a human eye but not visible to the scanner.
To check the grounding color of document for a drop-out color, use the method and follow the
standards given below.
Print density measurement
The spectrum chart shown in Figure 4.4 is used to measure print density.
The measurement must be made in one of the following ways:
• A light source using fluorescent.
• Macbeth PCS meter PCM II is used, which requires a filter.
Figure 4.4 Spectrum band
400
0
10
20
30
40
50
60
70
80
90
100
500 600 700
Waveength (nm)
Relative Spectral Power
Drop-out color standards
In the spectrum of fluorescent lamp the PCS value must satisfy the following standards:
• Maximum: 0.14 or less
• Average: 0.1 or less
09C4.P65 01.2.17, 5:44 PM8