Previously my rendering attempts have been relatively basic; I set up a sheet layer viewport, and then use the settings for the viewport to control how the render looks. But I know there are Renderworks cameras. Previously when I've dabbled with these I've got confused and given up due to lack of time but this morning I decided to brace myself and try and get my head around what they are for.   So, it seems they basically give you a greater range of controls over how your renders look