Canon Color imageRUNNER C4580, Service Manual

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Chapter 9
9-26
9.5.8 SALT-Dhalf Control (development characteristics correction)
The SALT-Dhalf control mechanism is used to stabilize the gradation of images on the ITB.
It makes up for the changes in gradation characteristics that occur in response to the deterioration in developer
or photopositive drum, changes in temperature/humidity, and changes that occur as the machine is used over
time.
Gradation Density Control for Half Speed
The control mechanism is used to make up for the changes in the gradation in images when thick paper,
special paper, or transparency is used.
When the mechanism is enabled in service mode, it is activated when auto control is executed.
The time it takes is about double the time taken when plain paper is used.
Description of Control
Start-up*
V
Measures the light reflected by the surface of the ITB (background measurement).
V
Forms a sample patch of a gradation pattern stored in the main
controller on the ITB.
V
Uses the SALT sensor to take a reading.
V
Performs density conversion (performs computation using the measurement taken).
V
Prepares an image correction table B/C (data processing).
V
End
- Non-AutomaticThe mechanism is executed when 'full correction'or 'quick correction' is under way in user
mode.
COPIER>OPTION>BODY>CAL-SW
Use it to change the conditions that initiate automatic control.
default: 0 (disable gradation density control for half speed)
F-9-20
SALT sensor
Bk
C
M
Y