Canon imagePRESS C1 Service Manual - page 383
Chapter 7
7-34
of M and Bk, measurements are performed while printing the second document, and the results will be reflected in the third printed document. In the case of 2-
image print, patch pattern measurement results of L, Y and C will be reflected not in the second but the third printed document as data processing takes more time.
F-7-40
7.4.16 PASCAL Control
0013-5521
imagePRESS C1 P / imagePRESS C1 / imagePRESS C1+ (Printer) / imagePRESS C1+
This machine provides two types of PASCAL control (image characteristics correction control); Reader PASCAL and Printer PASCAL.
- Reader PASCAL (3-page output paper):
Reads the 3-page output images at the reader unit and expresses them in ideal image characteristics by the PASCAL control (image characteristics correction con-
trol).
- Printer PASCAL (10-page output paper)
Expresses the output image in ideal image characteristics using two color sensors mounted in the duplexing feeding unit without using the reader unit, by the PAS-
CAL control (image characteristics correction control).
Memo:
This control is executed by the automatic gradation correction provided in the user mode.
Switch the Reader PASCAL and Printer PASCAL in the following mode.
System administration setting > Device administration setting > Automatic gradation correction > Method of automatic gradation correction
Reader PASCAL Control
This machine performs PASCAL control (image characteristics correction control) to express the image read by the reader unit in ideal image characteristics.
This control is performed in the main controller.
The printer outputs three test patterns (*1) based on the data in the main controller. The reader unit sequentially reads the output test patterns and the main controller
performs gradation correction to obtain ideal image characteristics.
In addition, in this control, the machine compares the electric potential contrast with the density value read by the reader, and performs D-max control (image density
correction control) to determine the contrast electric potential for the target density.
5-color full color (A4)
On the drum
Y
Y
L
L
M
M
C
1st page
C
Bk
Bk
Corrected data is reflected
2nd page
The gradation table for L is corrected .