Canon imagePRESS C1 Service Manual - page 376
Chapter 7
7-27
F-7-27
[1] Patch image data
[2] Density data
[3] D-half control
[4] Video data
PS3, PS4, PS76: patch image sensor
Operation Flow Chart
Below is operation flow chart of D-half control.
F-7-28
Memo:
The patch patterns produced in D-half control are as follows.
PS76
PS3
PS4
DC-CON
[1]
[3]
Laser Scanner
unit
[4]
MN-CON
[2]
Start-Up
Patch Patten Formation
Patch Scan
PS3, PS4, PS76
D-Half Correction Table Update
(Y, M, C, Bk))
Example: D-Half Correction Table for Yellow
Observed gradation
characteristics
Optimum gradation
characteristics
0
100
Density Data (DC-CON)
Y1
Y2
Y3
Data Output (MN-CON)
Y4
Y5
Y6
Y7
Y8
Y10
Y9
Patch Pattern Data Output
Main Controller
DC Controller
Main Controller
Density Data Output
100
D-Half Correction Table
Optimum gradation
characteristics
0
100
Density Data (DC-CON)
Data Output (MN-CON)
100
DC Controller