Appendix

Toner Low is displayed on the LCD when the number of dots or rotations of the developer roller nears its maximum count: Replace Toner is displayed on the LCD when the number of dots or rotations of the developer roller reaches its maximum count.

Color Correction

The number of developer roller rotations that are counted may not only be for normal operations such as printing, but also for machine adjustments, such as Color Calibration and Color Registration.

Color Calibration (Adjustment of Color Density)

To obtain stable print quality, the density of each toner cartridge needs to be maintained at a fixed value. If the density balance between the colors cannot be kept, the tint becomes unstable, and accurate color reproduction becomes unavailable. The toner density can change due to chemical changes to the toner that affect its electrical charge, deterioration of the developer unit, and temperature and humidity levels in the device. When calibration occurs, the density level adjustment test patterns are printed on the belt unit. Calibration is mainly performed at the following times:

• When the user manually selects calibration from the operation panel or the printer driver.

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(Please perform calibration if color density needs to be improved.)

• When a used toner cartridge is replaced with a new one.

•When the printer senses that the ambient temperature and humidity have changed.

•When a specified number of printed pages is reached.

Color Registration (Correction of Color Position)

In this device, the drum unit and developer unit are prepared for black (K), yellow (Y), magenta (M), and cyan (C), respectively. Four color images are combined into one image, and therefore color registration errors (i.e., how the four color images align) might occur. When registration errors occur, registration correction test patterns are printed on the belt unit.

Registration is mainly performed at the following times:

•When the user manually selects registration from the operation panel. (Please perform registration if a color registration error needs to be corrected.)

•When a specified number of printed pages is reached.

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