The Proof tool allows you to see on screen how your photo
will look when printed.
Unlike other tools, the proof tool is special. It is always applied to the entire photo and can not be masked using regions. Additionally, there can be at most one proof tool, it is always placed at the top of the tool stack, and its label can not be edited. Lastly, it is only in effect when shown.
Select the rendering intent you will use from the Rendering Intent pop-up menu.
Your photo will now appear on screen how it will look when printed.