ColorSync on Mac OSX
This page deals with Mac OS 10.1 as of February, 2002
The original form of this static report can be found on the Chromix website: [Here.]
ColorSync, Apple's system level Color Management System (CMS) has undergone a significant upgrade for Mac OSX For all previous versions of Mac OS, color management and ColorSync did very little for the user until an application was explicitly called on ColorSync to perform color matching tasks.(with the exception of Quickdraw GX, a minimally supported upgrade attempt at QuickDraw). Many Mac users remember the first time they opened their ColorSync control panel, changed some settings and then saw that nothing had changed on screen (again, in most cases). They may have concluded that color management doesn't work and left it behind.
Well, with Mac OSX, ColorSync has finally been upgraded to a first-class citizen and is built into the Quartz imaging system at the heart of OS X. This means that if an application simply calls on OS X to display an image, it will be color managed to the best of ColorSync's abilities. At a bare minimum this means that the display profile set in the ColorSync preference pane will be use as the destination for all color heading to screen. Which profile will be used as the source? That depends on the application (which can override ColorSync defaults) and whether or not there is a profile embedded in the image.
As the new print paths in OS X are also managed by Quartz, users run a greater chance of liking what they see coming out of their printers.
A few other points worth mentioning are
ColorSync 4 - the version installed with Mac OS X - supports ICC v4 profiles, an updated profile format standard that is emerging from the ICC and will start showing up on desktops in the months to come. Many color management settings are disappearing from the user interface. Sometimes it is tough to tell what is going on with the color on Mac OS X. The details of color settings are beginning to disappear from the user interface while the color is managed more easily and with better quality. This does not mean that those of us who make a living managing color are not made nervous by the apparent lack of control that is happening. Some of us cut our teeth on the down-and-dirty manual controls of Photoshop 4 (by plug-ins) and 5, ColorBlind Edit and other tools that allowed us to manage color but forced most users to learn more than they probably needed. Surely more than some wanted. At the moment (10.1.3) it is not possible to turn color management completely off in the non-postscript print path favored by most inkjet printers. This may make it tough to create custom profiles for these printers that can be used in the printer drivers themselves. You are able to create profiles of the print setup that can be used upstream in the print path - such as in Photoshop - but this may not always be optimal.
Suffice to say that while the basic functions offered by ColorSync to application developers have not changed drastically, the level of integration into the new OS is a new, wonderful, frightening, mystifying thing.
Check back with us regularly for updated notes and links regarding ColorSync 4 on Mac OS X, ICC v4 profiles and other advances and changes in the color management world. In the meantime, pay a visit to the link below for a technote from Apple that starts at a basic overview and moves all the way into the system calls developers can make to ColorSync. Stop reading when your head gets full.
Feb 28, 2002