I finished my work and I want to render everything. The object and the background. I use the nodes to cast a shadow on the background image. I did this thanks to a tutorial on youtube. But the guy doesn't show how to save or how to render this final image made with the nodes.
Here are my nodes with the final image in the background and the result I'd like to get in my render:
Here is the result I get when I press the Render button:
As you can see, it only rendered my renderlayer, which contains the mesh plane and the strange rock and that's not what I want...