<P> Script supervisors in film production used instant cameras as standard to aid visual continuity by photographing characters or sets, producing photographs that could be instantly referred to when a particular set or character's appearance needs to be reset and shot again, or recalled later due to the non linear shooting schedule of a film or television production (that is, a film is rarely shot in the order of chronology in the film, due to time, location or financial restraints). Script supervisors no longer use instant cameras due to digital technology . </P> <P> With the advent of digital photography, much of the instant camera's consumer appeal has been transferred to digital cameras . Passport photo cameras have gone to digital, leaving instant cameras to a niche market . </P> <P> Edwin Land's original idea behind instant photography was to create a photographic system that was seamless and easy for anyone to use . The first roll film cameras required the photographer to use a light meter to take a reading of the light level, then to set the exposure setting on the lens . Then the lens was focused and the subject framed and the picture was taken . The photographer flipped a switch and pulled the large tab in the back of the camera to pull the negative over the positive, through some rollers to spread the developing agent . After the picture developed inside the camera for the required time, the photographer opened the small door in the camera back and peeled the positive from the negative . To prevent fading, the black and white positive had to be coated with a fixing agent, a potentially messy procedure which led to the development of coaterless instant pack film . </P> <P> Pack film cameras were mostly equipped with automatic exposure, but still had to be focused and a flash bulb or cube unit needed to be used with colour film indoors . The development of the film required the photographer pull two tabs, the second tab which pulled the positive / negative "sandwich" from the camera, where it developed outside the camera . If the temperature was below 15 ° C (60 ° F), the positive / negative "sandwich" was placed between two aluminum plates and placed either in the user's pocket or under their arm to keep it warm while developing . After the required development time (15 seconds to 2 minutes), the positive (with the latent image) was peeled apart from the negative . </P>

When was the first polaroid instant camera invented