The None rendering intent
This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP.
The /None
rendering intent is a RIP extension that disables some aspects of color management while this intent is in effect. It is especially useful in jobs containing transparency effects and/or when OverprintPreview
is active in the color configuration. It is primarily intended for preserving CMYK values in page furniture.
It is set using the same operator used in Rendering intent:
/None setrenderingintent
Disabling color management in this context means:
- device space interception via the
Device*, Blend*,
andSource*
keyssetinterceptcolorspace
is ignored. - named color database resources is not used.
Other operators, and all other setinterceptcolorspace
keys are still honored. In particular, the Override*
keys still replace CIE-based spaces with the nearest device color space. Also, setreproduction
still takes effect, which includes /NextDevice
entries (for example, in the ink limiting configuration, https://hybridsoftwaregroup.atlassian.net/wiki/spaces/HQNCD/pages/55740111, CMYK values would have the ink limiting transform applied.
A common use is to avoid color managing page ornaments that typically appear outside the imaging area of the media, for example:
gsave
/None setrenderingintent
print_color_wedges
grestore
where print_color_wedges
is a customer written PostScript language procedure to print ornaments around the outside of the page.
This use of the /None
intent is similar to setting the above setinterceptcolorspace
keys to their default values of null. The main difference is with jobs that contain transparency effects. As explained in Transparency color management, color management occurs at each of a set of transparency groups, with many transparency pages requiring at least two transforms. Disabling the setinterceptcolorspace
keys only turns off color management in the first transform. Using the None
rendering intent in this way disables color management for the affected objects in all transparency groups.
Take care to ensure that the /None
intent is only used for local effects. In particular, it should not be in force during any call to setpagedevice.
If that happens, undefined effects on color and performance may occur, especially with jobs containing transparency effects. The recommended way to ensure the effect is always localized is to encapsulate all uses of it within gsave/grestore,
as in the above example.