Responsive section for banner/image/slider

I am currently testing the Enfold theme and I having trouble to get a section below the header to create a image/banner/slider with a fixed height but full width. This section must be responsive and must crop the image if the image is bigger trhan the section area. The image slider/banner must be responive if the screen size changes, but still full width and image zooms out or in if the screen changes size.
I cannot find the correct content area to do this. I always get or a background color besides the slider/image or image is full sized.
Also, is it possible to place a additional content area on top of this area, for example for another image or text box.