Triple Monitor Backgrounds

[jp734]

I have lubuntu 13.10 with three monitors using AMD Radeon card. How can I assign different backgrounds for each monitor or span one image. When I open "Desktop Preference" and select "Stretch to fill the entire screen" on wallpaper mode, it doesn't span. Instead all monitors will have the same background. There's no option to set different background for each as well.

Only options I have are:
- Stretch to fill the entire screen
- Stretch to fit the screen
- Center on the screen
- Tile the image to fill the entire screen

I opened Catalyst Control Center as well and don't see anywhere to set it.

[Frogs Hair]

I found a couple of triple monitor backgrounds on Google images, but they seem to be all 1080 in height . The longest being 5760x1080 and the duals run 3840x1080. http://4x.reddit.com/r/multiwall/

[jp734]

Thanks. Will sure check them out as I like collecting them. Still, the question is, how can I set these wallpapers to span on all three monitors?