The camera behind the camera is also called Quan Huafu camera.

The camera on the back of the machine is also called ground glass camera, technical camera and large format camera. Its main feature is that a large negative is used, the frosted glass on the back of the camera is used for focusing and framing, and the lens is connected with the back of the camera through a bellows cavity. The front lens plane and the back film plane can be adjusted by lifting, translating, pitching and swinging, so as to control the shooting effect. It is mainly used by professional photographers in the professional photography fields such as commercial photography, architectural photography, still life photography, landscape photography, photo plate making and so on. Cameras with camera backs can be divided into bulky monorail cameras and foldable portable dual-track cameras.

Its advantages are simple structure, large negative, large imaging, high definition and good detail recording ability; Different focusing lenses can be changed, so that the photographer can control the image to the greatest extent.

Its disadvantages are huge volume, heavy weight, complex adjustment and easy operation; In addition, the image on the ground glass is upside down, and the left and right are opposite, and the image brightness is also dark.

The main camera brands in the market are Swiss Chanel, German Lin Hafu, Japanese horsman and China Shen Hao.