While
            creating the key, you can view the composite using a solid colour
            for the background in place of the back clip. This can help you
            see details in the image, such as colour spill, that you may otherwise
            miss. You can use the default colour (black) or select a colour
            using the colour picker.
         
         NoteThis view does not
               affect the final render.
            
         To use a solid colour background:
         
         
            - In the View box, select Comp.
               A colour pot appears.
                NoteIf you colour corrected
                     the Front clip in the previous section, click RETURN in the Colour
                     Correction menu to access the Comp view option.
                   
- Click the colour pot above the Comp view
               output option.
               The colour picker appears.
                
- Select a colour for the background using
               the colour picker. See 
                           Colour Picker.