The PatchTool Select Compare window as it appears on Mac OS X; the window shows all opened files. PatchTool can compare two color lists which are defined by either spectral data, tristimulus data (i.e. XYZ, L*a*b*, RGB, etc.), CMYK data, or a mix of these file types. The two files must have the same number of patches. The resulting “Compare” window is similar to single file windows, but contains and presents the data of both files simultaneously, and offers additional tools which facilitate data comparison. When you place the mouse cursor in the “color ref.” column, you can see additional information on the file data. This information is shown below the table in green.