Panasonic KX-P8420 Manual

The RGB Source option is used to provide a source color space definition 
for RGB data in your document. The setting you specify for this option 
overrides any source color space profiles you may have specified using 
other color management systems. For example, if you specified a 
ColorSync System Profile on the Macintosh computer, the RGB Source 
setting specified in the Print dialog box overrides it. In cases where you 
don’t want this setting to override another specified source color space, 
select Off.

PostScript RGB data is converted to CMYK data using the CRD specified 
by the CRD option (see 

source color space information which is used as a reference point for the 
conversion.

NonPostScript RGB data is converted using a general under-color-removal 
conversion method. NonPostScript RGB data does not contain source color 
space information and so cannot be converted using a CRD.

The source color space defined by this setting is 
optimal for color conversions that will be sent to a 
KX-P8420 print device. It also allows for consistent 
output across different operating systems. 

The sRGB (PC) setting specifies the source space 
of a generic Windows computer monitor.

The Apple Standard setting specifies the source 
space of all standard Macintosh computer monitors.