What is the meaning of film House?
Unlike digital cameras, a film camera should allow you to charge and remove light-sensitive hardware without fogging it with light.
The oldest way to do this is by placing separate film sheets in a light-proof holder – a system still used for review cameras.
The double-sided stand slides to the rear of the camera, moving a focus display, then one side is open to face the lens.
Smaller cameras, however, use film in lengths to enable multiple exposures at one time.
The film passes from the supply to the return compartments behind a metallic chassis, flattened against it by a spring-loaded pressure plate.
It is protected from light during charging and offloading because the film is contained in a cartridge, or a cassette with a velvet feed slot that is "caught by the light."
The film is simply wound onto a reel with opaque backing paper.
Between exposures, a 35mm cassette film is wrapped through the camera on a permanently installed open coil.
It should be returned to its light-proof cassette before opening the camera to remove the film for processing.
Roll film does not require rewind; it wraps completely on an identical reel, is removable, taken protected by the last inches of backing paper.
Once inside the camera, the cartridge opens automatically and the film progresses; after the last exposure, the film is returned to the cartridge which closes again ready to be taken out.
Sheet film supports also let you change the content of your camera from one type of film to another at any time.
If you want to do the same thing with a 35mm camera or roll film without wasting the images, it is faster to use two bodies, change the lens from one to another, or use a camera built with interchangeable film magazines.
Most cameras with magazine backs also support instant photo film packing media.
The film lengths are offset through the camera either by an electric motor fired immediately after closing the shutter after each exposure, or manually using a wind lever.
The wind, shutter, and exposure release are normally locked so that you cannot take another picture until the previous shot has been rolled up, and vice versa.
Certain cameras provide a button to hover over the system for special overlay effects.
Older mid-format cameras do not turn on automatically: You must remember to take a breath after every shot – a little window on the back of the film tells you the number of shots you made, and you may need to restore a black layer between exposures to prevent light from reaching the film.