some help with a seemingly easy thing

[t3tsubo]

my friend made a really cool effect with his picture, and i want to know how to copy it. however, being the ass that he is, he wont tell me how.

http://i7.photobucket.com/albums/y253/Th_tetsubo/Invert1scanlines.jpg

now the scanlines i know how to do, but that half inverted half normal thing is what id like to figure out how to do. supposedly he used the gradient tool, but i really dont get it :mad:

[Chonny99]

Set to Difference at 100% to start with, if it doesn't fall the way you want click on the reverse button to flip the gradient. And try different combinations of color gray to white etc. and opacities.

[t3tsubo]

thanks for the help, its very much appreciated. time to kik my friends ass :D