Using the Subtract mode
How to do it…
This simple recipe will show you how to change a layer mode to the Subtract mode:
In the Layer palette, click on the layer to edit (if the Layer palette is not visible, go to Window | Layer to open it).
In the top-left corner of the Layer palette, click on the drop-down menu. Then, click on the Subtract mode.
How it works...
The colors in the top layer (the layer being adjusted) are subtracted from the layer below it. Our white-filled rectangle has changed to solid black. The blue vertical line has become light orange where it overlaps the white paper color; where it overlaps yellow, it has become medium orange; and where it overlaps purple, it has changed to a purple-red color. The dark red vertical line has become light blue where it overlaps the white areas, and where it crosses the yellow stripe, it is light green. Where it crosses the purple line, it has become medium blue.
