By Sue Chastain
Color Libraries Button
You'll also see a color libraries button below the OK and Cancel buttons in the color picker. This is used by professional designers who need to use specific brand-name color libraries for process printing.
To pick a color from a part of your screen outside of Photoshop, move your cursor outside of the color picker and onto an open image, just like I described above. But instead of clicking and releasing the mouse button, click and keep the mouse button held down. While keeping the mouse button held down, move the cursor outside of the Photoshop workspace to an area of the desktop. As you move over the desktop, you'll see the new color box in the color palette change to whatever color is under the eyedropper cursor. When you're hovered over a color you want to use in Photoshop, release the mouse button and the color picker will jump to that color.