The basic science behind the movies is all about how our eyes and brains work.
When our eyes sees a series of still images in quick succession, each image is hold of a while after it disappears and even as next one starts to replace it. These two images blur together to make a single moving image. This is known as Persistence of Vision.
In 19th century toy makers use the concept of persistence of vision to make new toys. One such toy was called zoetrope. It is a rotating drum, inside of which a long strip of paper with pictures drawn to it. Then you rotate the drum to make the pictures blur together and looked down through the slits to watch them. You have noticed this toy in latest movie Conjuring, in this movie Janet and her brother plays with it.
Classical movie cameras are largely mechanical and capture images on moving plastic film. Modern video cameras and camcorders work more like digital cameras and capture images digitally instead. In a standard film camera, you have to wind the film on so it advances to the next position to capture another photograph. But in a movie camera, the film is constantly moving and the shutter is constantly opening and closing to take a continuous series of photographs-about 24 times each second.
The unexposed movie film starts out on the large reel at the front and it is passed over guide rollers and spring –loaded pressure rollers that hold it firmly against the central sprocket. The sprocket’s teeth lock into the holes on the edge of the film and pull it precisely and securely through the mechanism. The light from the scene being filmed enters through the lens and passes into a prism, which splits it in half. Some of the light continues on through the shutter and hits the film, exposing a single frame of the movie. The rest of the light takes the lower path, bouncing down to a mirror. The shutter is like a mechanical eyelid that blinks open 24 times a second. The shutter is driven by same mechanism that turns the sprocket. More pressure rollers hold the exposed film against the lower part of the central sprocket. The teeth on the sprocket pull the exposed film back through the camera. Light redirected by the mirror exits through the lens and viewfinder so the camera operator can see what he is filming. The guide rollers take the exposed film back up toward the upper reel. The large upper reel at the back collects the exposed film.
When video recording was invented, photographic film was replaced by the magnetic video tape, which was simpler, cheaper, and needed no photographic developing before you could view the things you have recorded. Modern camcorders use a light sensitive microchip called Charge Coupled Device(CCD), to convert light coming through the lens into numerical format. The more working of the digital camera is presented in our article Digital Cameras.
When our eyes sees a series of still images in quick succession, each image is hold of a while after it disappears and even as next one starts to replace it. These two images blur together to make a single moving image. This is known as Persistence of Vision.
In 19th century toy makers use the concept of persistence of vision to make new toys. One such toy was called zoetrope. It is a rotating drum, inside of which a long strip of paper with pictures drawn to it. Then you rotate the drum to make the pictures blur together and looked down through the slits to watch them. You have noticed this toy in latest movie Conjuring, in this movie Janet and her brother plays with it.
Classical movie cameras are largely mechanical and capture images on moving plastic film. Modern video cameras and camcorders work more like digital cameras and capture images digitally instead. In a standard film camera, you have to wind the film on so it advances to the next position to capture another photograph. But in a movie camera, the film is constantly moving and the shutter is constantly opening and closing to take a continuous series of photographs-about 24 times each second.
Source:gridclub.com
The unexposed movie film starts out on the large reel at the front and it is passed over guide rollers and spring –loaded pressure rollers that hold it firmly against the central sprocket. The sprocket’s teeth lock into the holes on the edge of the film and pull it precisely and securely through the mechanism. The light from the scene being filmed enters through the lens and passes into a prism, which splits it in half. Some of the light continues on through the shutter and hits the film, exposing a single frame of the movie. The rest of the light takes the lower path, bouncing down to a mirror. The shutter is like a mechanical eyelid that blinks open 24 times a second. The shutter is driven by same mechanism that turns the sprocket. More pressure rollers hold the exposed film against the lower part of the central sprocket. The teeth on the sprocket pull the exposed film back through the camera. Light redirected by the mirror exits through the lens and viewfinder so the camera operator can see what he is filming. The guide rollers take the exposed film back up toward the upper reel. The large upper reel at the back collects the exposed film.
When video recording was invented, photographic film was replaced by the magnetic video tape, which was simpler, cheaper, and needed no photographic developing before you could view the things you have recorded. Modern camcorders use a light sensitive microchip called Charge Coupled Device(CCD), to convert light coming through the lens into numerical format. The more working of the digital camera is presented in our article Digital Cameras.
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