Various broadcast cameras in the market have a setting that will improve the keying quality by Chromatic Aberration Compensation. This setting is only available for Broadcast Cameras which support CLASS (Chromatic Aberration and Sharpness Solution). Lens keeps this information and if your camera also supports, this setting can be activated following the steps below:
Go to System Menu > Configuration > Lens > Lens Corrections and change the STATUS to Active as shown below. You will notice the difference in keying once this setting is enabled and if you are using a wide lens, the chromatic aberration compensation will be more visible.
The menu for Lens Corrections might be different for the camera you are using. This menu path shown here is valid for the Grass Valley Camera LDX86 N series which supports CLASS.