Tutorial to Make Scanlines in Photoshop

Scanlines are a pretty awesome thing to put on Graphics, I use them alot.
Again, this is probably a bit basic, but tutorials pwn, so I'll make it anyways.
This should work in most if not all versions of Photoshop,
but for demostration purposes, I'll be using Photoshop CS4.

Firstly, you need an image to apply the effect to, obviously.
I will be using this picture of a beautiful sunset (:



So first of all, open your image in Photoshop (this can be done on graphics too,
just add the scanlines when you want them). Then, create a new image with these settings:



When you've done that, press Ctrl&+ to zoom into the image to the maximum you can zoom into.
When you can't zoom any further, select the pencil tool, the colour you want the scalines to be.
Make sure it is set on pixels: 1. Then draw a pattern like this: (Or you can experiment with your own.).



When you've drawn the pattern, select Edit on the top, then on the dropdown menu select 'Define Pattern'.
Then, give it a name, something like 'Scanlines' and click OK.
Now, go back to your picture (for me, the sunset). On the top, select Edit, and on the dropdown menu select 'Fill'.
A box will popup. In the use section, select 'Custom Pattern'. Then select the scanline pattern.
You can change the opacity accordingly, But I'm going to be using 15%.



When you're done, click OK. If the scanlines are too dark/light for you, redo the step and change the opacity.
You can experiment with opacities and see the result. For me, this was my result:



There are lots of different Patterns...
So experiment like crazy! You can change the size of the 3x3 sqaure so you can fit more in.
These are like tiles, and there are endless possibilities.