Ground Glass

The image passes through the camera's lens and is diverted via a mirror before being focussed onto the ground glass which enables the camera operator to view the image. The camera operator is in fact looking at an image which is projected onto the ground glass. The ground glass is also marked with the aspect ratio of the format being used and sometimes has a safe title area or a centre cross to help with framing. For example you would order a super 16 camera with either a super 16 or an academy ground glass depending on which aspect ratio you were shooting in.