What is the difference between device side editing and PCS side editing and what is the benefit of selecting one or the other?
Editing on the PCS side allows the edits to be device independent. This allows the same edits to be used to change other device profiles. With device side editing, the changes are only accurate for that particular ICC profile and device combination. Page 84 of the version 3.1Custom Color Tools User Guide has a table that explains where the editing is done, and gives some setup information. Here is an example of using device side editing to solve a common CMYK problem; when the original profile will not convert a perfect white to 0% cyan, magenta, yellows, and black dot. For this example let’s use a combination of C1, M0, Y1 and K0 and change the 1% cyan and magenta to 0%. To do this you must edit on the device side of the profile and move the 1% dots to 0%. This type of edit cannot be done working on the PCS side of the profile because the profile may already be seeing what it considers to be a perfect white as far as PCS goes: L* 100, a*0, and b*0. In this example, you cannot make the
