What if we need lots and lots of thin focus lines? The Dense saturated line tool is the go-to tool for that job!
The following steps will teach us how to use the Scattered saturated line tool:
Select the Figure(U) tool from the toolbox. Then go to Saturated line | Dense saturated line.
Click on the spot where you want all the lines to radiate from and hold down the mouse button.
While still holding down the mouse button, drag out to form an ellipse around the area to focus on. In the following screenshot, the lines will be focused on the character's face. Because this tool makes such dense lines, I try to go a long way around the area that I want the focus to be on so that it doesn't get obscured by the lines.
Release the mouse button to generate the lines.