Image Gradation And Bit Data Size; Scanner Cartridge Detection; Calibration Operation Based On The White Calibration Sheet; Scanning Time And Data Size (Reference) - Canon BJC-3000 Service Manual

Part 5: Appendix

1.5.3 Image gradation and bit data size

Refer to the description below for the relationships between the image gradation and
the bit data size.
a) 256-gradation/8-bit data/multi-value
256-gradation is processed by 8-bit data. Within the scanner, the image processing
unit in the scanner controller normally processes the 8 bit data. 256-gradation can
also be referred to as the multi-value.
b) 2-gradation/1-bit data/2-value
2-gradation (monochrome) is processed by 1-bit data. Within the scanner, the image
controller unit in the scanner controller processes the data in 2-gradation. When the
monochrome processing is selected, data with 256-gradation will be processed as 2-
gradation data in monochrome by the prescribed threshold value after the normal
processing of 8-bit data is completed.

1.5.4 Scanner cartridge detection

The scanner cartridge detection within the printer is performed by DIA, DIK, and
SCHKR. The internal register setting within the scanner cartridge between DIA and
DIK is 5.6K ohms, and between DIK and SCHKR is 22K ohms.

1.5.5 Calibration operation based on the white calibration sheet

In the calibration process, data such as the printer's internal temperature, black level
data, and white standard data are sampled to be used as a reference in scanning, to
create the calibration data.
The scanner driver on the host computer retains the past 5 calibration data samples
and saves them in a file.
When a scanner operation is performed, a value from the compiled temperature data
that is within ±5°C of the printer's internal temperature at present is downloaded to
the scanner controller.
The scanner driver requests calibration when there is no compiled data within ±5°C.

1.5.6 Scanning time and data size (reference)

The scanning time and scanning data sizes are listed below.
When the scanning data sizes are stored into the files, the scanning data sizes are
varied with the file format.
Measurement Conditions
· Host computer: DELL XPS T550 (Pentium III 550MHz, internal memory 256MB)
· Interface:
· Paper size:
· Scan time:
TABLE 5-4 SCANNING TIME AND DATA SIZE (REFERENCE)
Scanning resolution
(H V)
720
360
180
90
Parallel interface, ECP mode
A4
from the start of the paper feed operation to ejection
Color
Color
720 Approx. 25Min.08Sec. Approx. 6Min.57Sec. Approx. 3Min.05Sec.
137261 KByte
360 Approx. 6Min.39Sec. Approx. 1Min.41Sec.
34315 KByte
180 Approx. 3Min.16Sec. Approx. 1Min.09Sec.
8576 KByte
90 Approx. 3Min.09Sec. Approx. 1Min.03Sec.
2143 KByte
Scanning Modes
Black & White
Gray Scale (8bit)
45753 KByte
11438 KByte
2858 KByte
714 KByte
5-14
BJC-3000
Mono (1bit)
5719 KByte
Approx. 50Sec.
992 KByte
Approx. 32Sec.
357 KByte
Approx. 27Sec.
91 KByte