The following instructions explain how to perform the white balance adjustment on the iMac (Summer 2000 and Slot Loading) computer.

DANGER! This procedure exposes you to high voltages that can result in death or serious injury. DO NOT ATTEMPT THIS PROCEDURE IF YOU HAVE NOT BEEN CERTIFIED AS AN APPLE-AUTHORIZED TECHNICIAN.

Products affected

• iMac (Slot Loading)
• iMac (Summer 2000)

Tools Required

• Display Adjustment Utility (DAU)
• jumper adjustment tool (922-4165)
• light meter Model R77 (076-0310)

Procedure

1. Note : Before you begin, make sure the:
   • cutoff is set correctly.
   • monitor has been on for at least 10 minutes.
   • jumper adjustment tool is connected to the video board (refer to article 95104 below).
   • room is dimly lit.
   
   
2. Open the Display Service Utility and select the Gray Bars test pattern from the Pattern menu. See Figure 1.
   
   
   Figure 1 Pattern Menu-Gray Bars
   
   
3. Adjust the red, green, and blue drive controls until there is no predominant color. See Figure 2.
   
   
   Figure 2 Drive Controls
   
   
4. Select "White" from the Pattern menu to display the all-white test pattern See Figure 3.
   
   
   Figure 3 Pattern Menu- White
   
   
5. Hold the light meter against the center of the all-white screen. The screen luminance reading should be 33± 5fc (foot candles) on the light meter Model R77. If the luminance readings are not within spec, verify the meter is functioning correctly.
   
   
6. Click the Save button on the Display Adjustment Utility screen to save your settings. See Figure 4.
   
   
   Figure 4 Display Adjustment Utility-Save Button
   
   
7. Restart the computer and reset the parameter RAM (PRAM) to apply the newly saved cutoff and white balance adjustments to the Factory Setting. To reset the PRAM, hold down the Command-Option-P and R keys after Restart is selected from the Special menu. Note: If you don't restart the computer, the iMac will display the last settings made on the iMac.
   
   
8. Open the Monitors control panel. Select the Geometry icon. See Figure 5.
   
   
   Figure 5 Monitor Control Panel
   
   
9. To complete the adjustment, click the Factory Settings button. See Figure 6.
   
   
   Figure 6 Factory Settings Button
   

Related Articles

• article 95104: iMac: Light Meter and Video Adjustment Tool Setup
• article 95105: iMac: Focus Adjustment
• article 95106: iMac: Screen Voltage Adjustment
• article 95107: iMac: Cutoff Adjustment
• article 95109: iMac: Geometry Adjustment
• article 95110: iMac: S Correction Adjustment