You can easily remove unwanted elements of your scene, including render materials, lights, foregrounds, backgrounds, and other scenery.
To remove elements of your scene,
1. Click the Scene tab in the Rendering Browser
2. Click Current Scene at the top of the browser pane to expand and view the materials, lighting, and scenery components currently assigned.
3. Right-click the material, light studio, or scenery element you wish to remove.
4. Click Delete.
5. Click Yes in the confirmation dialog. The element is deleted from the current scene only, and not from the Rendering Browser.
Replacing a scene component will remove the previous component. For example, if you assign a new background to your scene, the previously assigned background is replaced and removed from the Current Scene folder.