N-Color XG profiles

This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP

The recommended workflow for XG devices is to use a wide gamut CMYK exchange space, see Wide gamut CMYK exchange space .

The direct use of N-color profiles may result in implementation difficulties outlined in XG Color Management , and is not recommended. If they are used, this is a possible configuration; it is a re-purposing workflow modified to use N-color profiles and ink limiting:

CODE

<<
  /DeviceCMYK [ /ICCBased (iccprofiles/SWOP.icc) (r) file ]
  /DeviceRGB [ /ICCBased (iccprofiles/sRGB.icc) (r) file ]
  /OverprintPreview /SpotsOnly
>> setinterceptcolorspace

<<
  /Profile (iccprofiles/CMYKOG.icc) (r) file
  /NextDevice <<
    /InputColorSpace [
      /CMM
      (ink-limiting-CMYKOG-240)
      [ /DeviceN [/Cyan /Magenta /Yellow /Black /Orange /Green] /DeviceCMYK {pop pop}]
      [ /DeviceN [/Cyan /Magenta /Yellow /Black /Orange /Green] /DeviceCMYK {pop pop}]
    ]
  >>
>> setreproduction

In our experience an ink limiting transform will be required to avoid expensive machine failures. The ink limiting could be built into the N-color profile, or as illustrated, it could be via an additional /NextDevice. In the example it’s implemented in the (ink-limiting-CMYKOG-240) CMM custom color space, which accepts the six device colorants for input and output. It is probably desirable to offer a small number of different levels of ink limiting for use with different classes of media.

The SpotsOnly mode of OverprintPreview (see Understanding OverprintPreview) may be used with the above example. However, when converting directly to an XG profile, the use of SpotsOnly requires that the device space of the XG profile contains all CMYK colorants. If the device space doesn't contain CMYK, the RIP will silently revert OveprintPreview to the Inactive mode (see Inactive mode).