Ricoh B264 Service Manual page 296

SERVICE PROGRAM MODE TABLES
4904* IPU Setting
Many IPU setting SP modes have discussions in section 6. ( 6.5)
4904 1* Grayscale Photo Mode
Selects the method of grayscale processing for the Photo Mode.
"Dithering and smoothing" is the same as the setting for "Print Photo" selected on
the operation panel in Photo Mode. Dithering can be adjusted with SP4903 037.
"Error diffusion and MTF filter processing" is the same as the setting for "Normal"
or "Glossy Photo" selected on the operation panel in Photo Mode. Error diffusion
can be adjusted with SP4903 036 and 038.
4904 2* Quality Photo Mode
Selects the size of the dither matrix for the photo mode.
4904 3* Density Setting for Low
Density Original Mode
Selects the density γ factor for the low-density original mode.
Use to achieve better balance between text and images, correct shadows that
appear around text in handwritten documents, to enhance documents written in
pencil, or to achieve stark contrast when copying blueprints, building plans, etc.
4904 4* Density Setting for Copied
Original Mode
Selects the density γ factor for the copied original mode.
4904 5* Special Text Density
Enter the appropriate number with the 10-key pad then press . This SP code
adjusts the density of the image to eliminate vertical black lines in originals that
were caused by previous scanning with a dirty optics.
While selecting a higher setting to erase more lines, selecting a very high setting
can cause low contrast areas to become faint or cause them to drop out. ( 6.5)
4904 7* Error Diffusion Pattern
Adjusts the threshold level for error diffusion processing in the Text/Photo mode.
The effect of error diffusion can vary, depending on the image of the original.
Adjust this setting if the results of the texture in copies is not what you expect,
especially before starting a large copy job.
4904 8to 4904 12, Gray Adj.: Text/Photo (Edge Det.), Photo (Edge Det.)
The following 5 SP modes adjust the setting for edge detection during grayscale
processing of originals scanned with the Custom Setting of the Text/Photo mode
and Photo mode in the specified magnification range. At defined edges error
diffusion executes on text to create sharp lines to better define text characters, but
in other areas, error diffusion executes grayscale processing for photographs.
Select a lower setting for better reproduction of photographs and a higher setting
for sharper text. A lower setting improves the appearance of photographs, but can
cause text and thin lines to drop out. A higher setting sharpens text and thin lines,
but can also cause grayscale areas to degrade. ( 6.5)
4904 8* Gray Adj: Text/Photo (Edge Det.) 25-64%
B264/B265
0: Dithering and smoothing
1: Error diffusion and MTF filter processing
Value Method
0 4-Value Error
Diffusion
1 Dither 8x 8
3 Dither 8x 8
2 Dither 6 x 6
4 Dither 4 x 4
0: Selects γ normal density
1: Digitizes to near binary image
0: Selects γ normal density
1: Digitizes to near binary image
[0~7 / 0 / 1]
0: Off, 1: Weaker, 7: Stronger
0: Edge threshold pattern is used.
1: Texture Pattern (matrix) 0 is used
2: Texture Pattern (matrix) 1 used.
3: Texture Pattern 2 (matrix) used.
[0~15 / 8/ 1]
5-32
Lines Effect
--- Best resolution
75 Screening
106 Best grayscale
142 Grayscale priority
212 Resolution priority
SM