When connecting Mac via HDMI cable, the monitor may show incorrect color and non-smooth tone.

 

In details, phenomena occurs such as:

 - High tone/low tone cannot be displayed correctly

 - Middle tones are skipped.

When these occur, we recommend using alternative ways than HDMI connection.

 

- Cause

Mac does not output full range, RGB signal but limited range, YUV signal from the HDMI port. 

This is an intended behavior of Mac. 

 

- Measures

1. Use alternative connection than HDMI.

 

    When Mac has following output connectors, please use these connectors.

　  - Thunderbolt 3 (USB Type-C)

　  - Thunderbolt 2 (Mini DisplayPort)

　  - DVI

 

2. Change the monitor settings (ColorEdge monitor only)

 

    You can avoid this HDMI issue with the following "Signal Format" setting.

 

     For CG277 / CG247 / CG247X / CX271 / CX241 / CS270 / CS240

      Optional Settings -> Signal Selection -> Signal Format -> HDMI

      Change the setting to "PC"

 

     For CG2700X / CG2700S / CG2730 / CG2420 / CS2740 / CS2731 / CS2730 / CS2400S / CS2420 / CS2410

      Administrator Settings -> Signal Format -> HDMI

      Change the setting to "PC" or "RGB" or "4K 60Hz"

 

    Please refer to the user's manual for detailed procedure.