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*, and Source* keys setinterceptcolorspace 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, Ink limiting, 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.