Scroll down effect for picture

Hi,

I would like to add a picture with a special effect like it is used at the home page “gradient header” of Fortuna: http://blueowlcreative.com/wp/fortuna/home-page/home-gradient/. If you scroll down, the picture appears and disappears. (e.g. the picture with the computer)
For my home page I use the template “full width slider 3″ and I only want to create this effect for one of the pictures on the page.
Is there a special effect for that?

Thank’s a lot!