Applicable Monitors：ColorEdge CG277, CG247, CG246, CX241 (US models only)

1. Details                                                                  

When connecting the monitor via DisplayPort to a Mac Thunderbolt port with Mac OS X 10.7 or OS X Mountain Lion (10.8), black tones display lighter and white tones display darker.
This is due to the YUV limited range signal of the Mac and monitor displaying the screen without range extension.

2. Measures                                                                 

2.1 OS update

Update Mac OS to OS X Mavericks (10.9) that outputs RGB full range signal.

2.2 Change the signal bandwidth setting

If updating the Mac OS is not available, change the signal bandwidth setting from "Wide" or "Wide 1" to "Normal" that outputs the RGB full range signal.