cycling dual screen?

I'm trying to get the cycling background to extend onto both displays so i will have one continuous background rather than two identical ones. all my wallpapers are dualscreen, but windows is displaying them all smashed together on both displays. It worked one boot up, and im unable to make it reoccurring. I've checked what i think are all the menus, but i cant seem to find any option that changes that. im almost positive i can accomplish this without a third party app.

Pretty sure that it works if you set your wallpapers to tile. It only looks good if you have wallpapers for your exact res though.

Thanks alot, I'm glad it was really simple. and I don't really know why I never tried all the settings. thanks again.