Comparing Colour Profiles
Ever wonder why when you convert an image from RGB to CMYK, the colour appearance can be so dramatically different?
One way to understand why this happens is to compare the colour space gamuts of different devices (such as a display and a printer). You can do this by using the ColorSync Utility.
Step 1: Open the ColorSync Utility, located in the Utilities folder in the Applications folder and click Profiles in the toolbar.
Step 2: In the left column, select the colour profile of your first device. You’ll then see in the bottom-right space a 3D model called a “lab plot”.
Step 3: Click the downward-pointing triangle on the top-left corner of the lab plot and from the pop-up menu choose “Hold for Comparison”.
Step 4: Then click the profile of another device in the left column.
You’ll now see the colour profiles of the two different devices laid on top of each other. The first profile that you held for comparison is the lighter of the two.
Comparing the 3-dimensional gamut of the selected profiles shows you how converting from one colour space to another can affect the colours of your image. The areas where one gamut exceeds the boundaries of another are known as “out of gamut”. It’s these out-of-gamut colours — which cannot be reproduced within the target colour space (or on the target device) — that cause the difference in colour appearance when converted from one colour space to another.
