Before/after viewer

We are looking for an html 5/flash developer to create a windows for an existing website that can show the progression of the manipulation (retouching) of an image. This will need to be shown in the window using a side scroller at the bottom of the image to allow the user to control the separate stages of the manipulation of the image to to see the transition between each stage. A strong example of what we are looking for can be found at this link [login to view URL] - once you have accessed this website please click the 'making of' tab at the top of the page. The important aspect of the slider is that it gives a fade effect between the transitions of the manipulation to the image shown in the window. We want something that looks sleek and simple and is easy to use. x 5