Having been confused with ColorSync in the past, I recently went back to Apple's ColorSync web page apple.com and now have to admit:

• I think Apple got ColorSync right under Jaguar (for Photoshop and color–managed applications that honor embedded profiles).

But first, What is ColorSync? gballard.net.

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The following is an example ColorSync workflow for Photoshop under Panther 10.3, Jaguar 10.2.

While I still recommend a "US Prepress Defaults/Adobe(ACE)/AdobeRGB" Photoshop workflow for prepress, I can see how a "ColorSync workflow" can make colour management easier for regular users because:

The ColorSync panel sets the workflow, and the workflow can be enabled with "one shot" in many applications, including Adobe Photoshop 6 7 8 CS.

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First, build a good monitor profile at 2.2 gamma, see my get a good screen.

Set ColorSync Default Document Spaces:

9.2: System Folder> Control Panels> ColorSync> Profiles> Default Profiles for Documents:
10.2: System Preferences> ColorSync panel> Default Profiles Tab:
10.3: Applications> Utilities> ColorSync Utility panel> Preferences Tab:

RGB Default: sRGB IEC61966-2.1 (this is your preferred Document/File ColorSpace)
DO NOT SELECT YOUR MONITOR PROFILE HERE!

The System and Photoshop get the monitor profile from: System Preferences> Displays panel> Color tab> the highlighted monitor profile.

CMYK Default: US Web Coated SWOP v2 (or your preferred Document CMYK)

Gray Default: 2.2 gamma (or your preferred Gray)

CMMs Tab: Preferred CMM: Apple CMM

Notice (below) that ColorSync's Default RGB and CMYK appear in Photoshop's Working Spaces when Photoshop's "ColorSync Workflow" is selected.

In other words, ColorSync Color Management System (CMS) sets its "WorkingRGB, WorkingCMYK, WorkingGRAY" in its panel — the same as — Photoshop does in its Color Settings panel.

WARNING: Some ColorSync–aware applications — iPHOTO, for example — do NOT Assume/Assign ColorSync's RGB Default to untagged files — even though the ColorSync panel's headline (above) says it does.

For example:
• When an untagged RGB file is opened in iPHOTO, ColorSync /Assumes/Assigns Jaguar's Default monitor profile to the file...in other words, if the photo was last saved (untagged) in the AdobeRGB ColorSpace, and opened in iPHOTO, ColorSync Assumes Jaguar's Default monitor profile to the untagged file and hoses the color — regardless of ColorSync's selected RGB Default.

In still other words — how iPHOTO hoses UntaggedRGB:

• If a scanner or camera captures the document (photo) in the sRGB ColorSpace, but does NOT embed a profile, ColorSync misAssigns, ASSUMES, Jaguar's Default monitor profile to the document and hoses the color when iPHOTO displays it. For more on testing this theory - please go to my sRGB Correct ColorSpace TUTORIAL and go down the page there to DOWNLOAD my iPhotoTESTfolder.sit test files tutorial. More advanced users may want to try my Assign Versus Convert to Profile Photoshop tutorial for the nutshell on how color managed applications like iPHOTO and Photoshop function.

• The ColorSync panel> Default Profiles tab headline is wrong, said John Gnaegy.
"I certainly understand why you would think (that ColorSync's RGB Default setting is Assigned to iPHOTO documents that do not contain embedded profiles), but that's not what happens. Untagged images are instead represented by the profile of the preferred (Default) display," said John.

• In other words, in my opinion, ColorSync/iPHOTO is broken for UntaggedRGB.

Because of this, I recommend using Photoshop to optimize the photos and Import them into iPHOTO, tagged, when finished.

Photoshop 6 7 8 CS:

Command+Shift+K (Photoshop> ColorSettings)>

Settings: ColorSync Workflow

• This sets Photoshop's WorkingRGB, WorkingCMYK by the ColorSync panel.
• This sets complete Photoshop Color Management Policies.
• This sets Photoshop's Color Management System to ColorSync.