IMAX (an acronym for image maximum) is a motion picture film format and a set of cinema projection standards created by Canadian company IMAX Corporation and developed by Graeme Ferguson,Roman Kroitor,Robert Kerr, and William C Shaw. IMAX has the capacity to record and display images of far greater size and resolution than conventional film systems.
During Expo 67 ,in Montreal, the National Film Board of Canada's In the Labyrinth and Ferguson's Man and the Polar Regions both used multiprojector, multi screen systems. Each encountered technical difficulties that led them to found a company called "Multiscreen", with a goal of developing a simplar approach. But later it became clear that a single large-screen image had more impact than multiple smaller ones and was more viable product direction, Multiscreen changed its name to IMAX.
Tiger Child ,the first IMAX film ,was demonstrated at Expo '70 in Osaka, Japan. The first permanent IMAX installation was bulit at Cinesphere theater at Ontario Place at Toronto.
The IMAX cinema process increases the image resolution by using larger film frame, in relative terms,a frame of IMAX format film has three times the theoretical horizontal resolution of a frame of 35mm film. To achieve such increase resolution ,which IMAX estimated at approximately 12 thousand lines of horizontal resolution (12k), 65mm film stock passes horizontally through the IMAX movie camera ,15 perforations at a time. At 24 frames per second(fps),this means that the film moves through the camera at 102.7 meters per minute (just over 6 km/hr). In a conventional 65 mm camera ,five perforations at a time or ,34 meters per minute.
The IMAX format of widescreen cinema , the movie image is taller than its wide ,given the film frame dimensions of 69.6mm × 48.5mm. To match the standard image resolution of the moving image produced with the film speed of 24fps, an IMAX film requires three times the lenght ofvfilm stock required for a 65mm film of comparable scope and cinematic technique.
In 2011 , IMAX announced a 4K 3D digital camera with the similar wide resolution of regular IMAX film cameras. The IMAX format is generally called "15/70" film, the name referring to the 15 sprocket ,holes or perforations per frame. The film's bulk requires horizontal platters ,rayheer than conventional film reels. The IMAX platters range from 1.2 to 1.83 meters diameter to accommodate 1 to 2.75 hours of film. Platters with a 2.5 hour feature film weigh 250 kilograms. IMAX uses ESTAR baed print film in their 15/70 rolling kiip film projection systems. ESTAR based print film provides greater precision.
In order to use the more area ,the IMAX film dies not include an embedded soundtrack. Instead ,the IMAX system specifies a separate six-channel 35mm magnetic film, recorded and played back on a film follower locked to picture.
Like conventional theaters , IMAX theaters place speakers both directly behind the acoustically transparent screen and around the theater to create a 'surround sound' effect. IMAX also provides a 'top center' speaker in addition to center' speaker found in conventional theaters. This extra channel allows the sound to mix engineers to take advantage of the screen's greater height.
To create illusion of depth ,the IMAX 3D process uses two separate camera lenses that represent the left and right eyes. The lenses are separated by a distance of 64mm ,the average distance between a human eyes. Two separate rolls of film are used to capture the images they produce. The IMAX 3D camera weighs over 113kg.
Variations on IMAX included the 48 fps IMAX HD process ,which sought to produce smoother, more lifelike motion, while also reducing the blurting of moving objects, by doubling the normal film rate. The IMAX HD system was tested in 1992 at Canada pavilion of the Seville Expo '92 with the film Momentum.
Source: www.London pass.com
IMAX is the most widely used system for special venue film presentations. There are over 1061 IMAX theaters in 67 countries.During Expo 67 ,in Montreal, the National Film Board of Canada's In the Labyrinth and Ferguson's Man and the Polar Regions both used multiprojector, multi screen systems. Each encountered technical difficulties that led them to found a company called "Multiscreen", with a goal of developing a simplar approach. But later it became clear that a single large-screen image had more impact than multiple smaller ones and was more viable product direction, Multiscreen changed its name to IMAX.
Tiger Child ,the first IMAX film ,was demonstrated at Expo '70 in Osaka, Japan. The first permanent IMAX installation was bulit at Cinesphere theater at Ontario Place at Toronto.
The IMAX cinema process increases the image resolution by using larger film frame, in relative terms,a frame of IMAX format film has three times the theoretical horizontal resolution of a frame of 35mm film. To achieve such increase resolution ,which IMAX estimated at approximately 12 thousand lines of horizontal resolution (12k), 65mm film stock passes horizontally through the IMAX movie camera ,15 perforations at a time. At 24 frames per second(fps),this means that the film moves through the camera at 102.7 meters per minute (just over 6 km/hr). In a conventional 65 mm camera ,five perforations at a time or ,34 meters per minute.
The IMAX format of widescreen cinema , the movie image is taller than its wide ,given the film frame dimensions of 69.6mm × 48.5mm. To match the standard image resolution of the moving image produced with the film speed of 24fps, an IMAX film requires three times the lenght ofvfilm stock required for a 65mm film of comparable scope and cinematic technique.
In 2011 , IMAX announced a 4K 3D digital camera with the similar wide resolution of regular IMAX film cameras. The IMAX format is generally called "15/70" film, the name referring to the 15 sprocket ,holes or perforations per frame. The film's bulk requires horizontal platters ,rayheer than conventional film reels. The IMAX platters range from 1.2 to 1.83 meters diameter to accommodate 1 to 2.75 hours of film. Platters with a 2.5 hour feature film weigh 250 kilograms. IMAX uses ESTAR baed print film in their 15/70 rolling kiip film projection systems. ESTAR based print film provides greater precision.
In order to use the more area ,the IMAX film dies not include an embedded soundtrack. Instead ,the IMAX system specifies a separate six-channel 35mm magnetic film, recorded and played back on a film follower locked to picture.
Like conventional theaters , IMAX theaters place speakers both directly behind the acoustically transparent screen and around the theater to create a 'surround sound' effect. IMAX also provides a 'top center' speaker in addition to center' speaker found in conventional theaters. This extra channel allows the sound to mix engineers to take advantage of the screen's greater height.
To create illusion of depth ,the IMAX 3D process uses two separate camera lenses that represent the left and right eyes. The lenses are separated by a distance of 64mm ,the average distance between a human eyes. Two separate rolls of film are used to capture the images they produce. The IMAX 3D camera weighs over 113kg.
Variations on IMAX included the 48 fps IMAX HD process ,which sought to produce smoother, more lifelike motion, while also reducing the blurting of moving objects, by doubling the normal film rate. The IMAX HD system was tested in 1992 at Canada pavilion of the Seville Expo '92 with the film Momentum.
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