Things you need:
1.Brain
2.Hands
3. Photoshop (Won't work with GIMP)



Here is how to do it:

1.Open up Photoshop(Any version).

2.Make a new 3x3 canvas

4.Zoom it how much you can by pressing Ctrl+Plus on the keyboard.

3.Click on brush tool and select Pencil tool.

5.Make 3 strokes(Dark)

6.Go to Edit>Define Pattern.

7.Give a name to the pattern and click ok.

8.Open the pic you want to add scanlines to.

9.Go to Edit>Fill.

10.Select the pattern. (Keep the options default) and Press ok

11. Done


Thnx go to Hobo Joey for teaching me this thing.

"5. Make 3 strokes"

Very unspecific and I'm fairly sure there's already a tutorial for this.

Edit: http://forum.toribash.com/showthread.php?t=139155

Closed.