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The IMAX® Film uses 15-perforation, 70mm film to shoot and project images of
incredible sharpness. The 15/70 frame is 10 times larger than the 35mm
used in regular theatres.
IMAX® DMR™
Extraordinary visual clarity and sound quality of IMAX
presentations transforms 35mm live action films through digital
re-mastering using IMAX's new patented proprietary software IMAX DMR.
SOFTWARE CREATES A FILM EXPERIENCE
IMAX digital re-mastering starts by converting a 35mm frame into digital
form at very high resolution, capturing all the detail from the
original. Our proprietary software mathematically analyses and extracts
the important image elements in each frame from the original grainy
structure to create a pristine form of the original photography. This is
the most complex step in IMAX digital re-mastering.
MEETING 35mm STANDARDS
The image on a 35mm film frame is comprised of a fine grain structure
like that of all photographic images. This grain when projected on to
the IMAX screen looks like a TV channel that isn't quite tuned to the
station. Removing this grain while preserving the quality of the
underlying image is the basis of IMAX DMR.
RE-MASTERED, REFINED and RESIZED!
To create the brightness and clarity that audiences have come to expect
from The IMAX Experience®, IMAX uses a proprietary computer program to
make the images sharper than they were originally, while colors are
adjusted for the unique technically superior characteristics of the IMAX
screen. The completed re-mastered film is then transferred onto the
world's largest film format, 15-perforations 70mm.
IMAX (short for Image Maximum) is a film format created
by Canada's IMAX Corporation that has the capacity to
display images of far greater size and resolution than
conventional film display systems. A standard IMAX
screen is 22 m wide and 16 m high (72.6 x 52.8 ft), but
can be larger. Currently, IMAX is the most widely-used
system for large-format, special-venue film
presentations. As of March 2007, there were 280 IMAX
theatres in 38 countries (60 percent of these are
located in the United States and Canada). The biggest
"IMAX Dome" is in Mumbai, India. Half of these are
commercial theatres and half are in educational venues.
A variation of IMAX, IMAX Dome (originally called
OMNIMAX), is designed for projection on tilted dome
screens. Films can also be projected in 3D with IMAX 3D.
Precursors
The desire to increase the visual impact of film has a long history.
In 1929, Fox introduced Fox Grandeur, the first 70 mm movie format,
which quickly fell from use. In the 1950s, Cinemascope and
VistaVision widened the projected image from 35 mm film, and there
were multi-projector systems such as Cinerama for even wider
presentations. While impressive, Cinerama was cumbersome and
difficult to set up, and the joints between the screens were
difficult to hide.
History
The IMAX system was developed by four Canadians: Graeme Ferguson,
Roman Kroitor, Robert Kerr and William C. Shaw. [1]
During Expo 67 in Montreal, Canada, In the Labyrinth, their
multi-projector giant-screen system had a number of technical
difficulties that led them to design a
single-projector/single-camera system. Tiger Child, the first IMAX
film, was demonstrated at Expo '70 in Osaka, Japan. The first
permanent IMAX system was set up in Toronto at Ontario Place in
1971, and is still in operation. During Expo '74 in Spokane,
Washington, a very large IMAX screen that measured 90 x 65 ft (27.3
x 19.7 m) was featured in the US Pavilion (the largest structure in
the expo). About 5 million visitors viewed the screen, which covered
a person's total field of vision when looking directly forward. This
easily created a sensation of motion for nearly everyone, and motion
sickness in a few viewers. However, it was only a temporary screen
for the six-month duration of the Expo. Several years later, a
standard size IMAX screen was installed, and is still in operation
at the renamed "Riverfront Park IMAX Theatre."
The first permanent IMAX Dome installation, the Reuben H. Fleet
Space Theater and Science Center, opened in San Diego's Balboa Park
in 1973. The first permanent IMAX 3D theatre was built in Vancouver,
British Columbia for Transitions at Expo '86, and is still very much
in use, as it is situated at the tip of Canada Place, a Vancouver
landmark.
[edit] Technical aspects
A comparison between 35 mm and 15/70 mm negative areas
A comparison between 35 mm and 15/70 mm negative areas
An IMAX camera inside a display case
An IMAX camera inside a display case
The 15 kW Xenon short-arc lamp used in IMAX projectors
The 15 kW Xenon short-arc lamp used in IMAX projectors
The intent of IMAX is to dramatically increase the resolution of the
image by using much larger film stock at a resolution comparable to
about 10000 x 7000 pixels. To do this, 70 mm film stock is run
"sideways" through the cameras. While traditional 70 mm film has an
image area that is 48.5 mm wide and 22.1 mm tall (for Todd-AO), in
IMAX the image is 69.6 mm wide and 48.5 mm tall. In order to expose
at standard film speed of 24 frames per second, three times as much
film needs to move through the camera each second.
Drawing the large-format film through the projector was a difficult
technical problem to solve; conventional 70 mm systems were not
steady enough for the 586x magnification. IMAX projection involved a
number of innovations. William Shaw of IMAX adapted an Australian
patent for film transport called the "rolling loop" by adding a
compressed-air "puffer" to accelerate the film, and put a
cylindrical lens in the projector's "block" for the film to be
vacuumed up against during projection (called the "field flattener"
because it served to flatten the image field). Because the film
actually touches the "field flattener" lens, the lens itself is
twice the height of the film and is connected to a pneumatic piston
so it can be moved up or down while the projector is running, this
way, if a piece of dust comes off the film and sticks to the lens,
the projectionist can switch to the clean side of the lens at the
push of a button. The lens also has "wiper bars" made of a felt or
brush-like material which can wipe the dust off the lens as it moves
up or down to keep the show clean. IMAX projectors are
pin-stabilized, meaning 4 registration pins engage the sprockets at
the corners of the projected frame to ensure perfect alignment. Mr.
Shaw added cam-controlled arms to decelerate each frame to eliminate
the microscopic shaking as the frame "settled" onto the registration
pins. The projector's shutter is also open for around 20% longer
than in conventional equipment and the light source is brighter. The
largest 12-18 kW xenon arc lamps have hollow, water-cooled
electrodes. An IMAX projector is therefore a substantial piece of
equipment, weighing up to 1.8 tonnes and towering at over 70" [178
cm] tall and 75" [195 cm] long. The xenon lamps are made of a thin
layer of quartz crystal, and contain xenon gas at a pressure of
about 25 atmospheres; because of this, projectionists are required
to wear protective body armour when changing or handling these lamps
because the flying shards of crystal could be deadly when combined
with the high pressure of the gas within.
IMAX uses a stronger "ESTAR" (Kodak's tradename for PET film) base.
The reason is not for strength, but precision. Developing chemicals
do not change the size or shape of Estar, and IMAX's
pin-registration (esp. the cam mechanism) is intolerant of either
sprocket-hole or film-thickness variations. The IMAX format is
generically called "15/70" film, the name referring to the 15
sprockets per frame of 70 mm stock. The bulk of the film requires
large platters rather than conventional film reels.
In order to use more of the image area, IMAX film does not include
an embedded soundtrack. Instead the IMAX system specifies a separate
six-channel 35 mm magnetic tape synchronized to the film. (This
original system--35 mm mag tape locked to a projector--was commonly
used to "dub" or insert studio sound into the mixed soundtrack of
conventional films.) By the early 90's, a separate digital 6-track
source was synchronized using a more precise pulse-generator as a
source for a conventional SMPTE timecode synchronization system.
This development presaged conventional theatrical multichannel sound
systems such as Dolby Digital and Digital Theater System. This
digital source came in the form of a unit called a DDP (Digital Disc
Playback) in which the soundtrack was recorded onto multiple CD-ROM
discs which would play the sound which was recorded to the discs as
a digital audio file. This DDP system has been replaced in almost
all theaters with the newer DTAC (Digital Theater Audio Control)
system which utilizes a computer running the IMAX's proprietary DTAC
software. The software works in a similar style as the DDP except
that instead of the audio file being based on discs, it is instead
played directly off a hard drive in the form of a single
uncompressed audio file containing the 6 channels which are
distributed directly to the amplifiers rather than using a decoding
method such as Dolby Digital.
IMAX theater construction also differs significantly from
conventional theaters. The increased resolution allows the audience
to be much closer to the screen; typically all rows are within one
screen-height. (Conventional theaters seating runs 8 to 12
screen-heights) Also, the rows of seats are set at a steep angle (Up
to 23 degrees in some domed theaters) so that the audience is facing
the screen directly.
[edit] IMAX Dome/OMNIMAX
The frame layout of the IMAX Dome film.
The frame layout of the IMAX Dome film.
The Control room of an IMAX Dome Theatre.
The Control room of an IMAX Dome Theatre.
In the late 1960s the San Diego Hall of Science (now known as the
Reuben H. Fleet Science Center) began searching North America for a
large-format film system to project on the dome of their planned
76-foot tilted-dome planetarium. One of the front-running formats
was a double-frame 35 mm system, until they saw IMAX. The IMAX
projector was unsuitable for use inside a dome because it had a
12-foot-tall lamphouse on top. However, IMAX Corporation were quick
to cooperate and were willing to redesign their system. IMAX
designed an elevator to lift the projector to the center of the dome
from the projection booth below. Spectra Physics designed a suitable
lamphouse that took smaller lamps (about 18 inches long) and placed
the bulb behind the lens instead of above the projector. Leitz of
Canada developed a fisheye lens that would project the image onto a
dome instead of a flat screen.
The dome system, which the San Diego Hall of Science called OMNIMAX,
uses a fisheye lens on the camera that squeezes a highly distorted
180 degree field of view onto the 70 mm IMAX film. The lens is
aligned below the center of the frame and most of the bottom half of
the circular field falls beyond the edge of the film. The part of
the field that would fall below the edge of the dome is masked-off.
When filming, the camera is aimed upward at an angle that matches
the tilt of the dome. When projected through a matching fisheye lens
onto a dome the original panoramic view is recreated. OMNIMAX wraps
180 degrees horizontally, 100 degrees above the horizon and 22
degrees below the horizon for a viewer at the center of the dome.
OMNIMAX premiered in 1973 at the Reuben H. Fleet Space Theater and
Science Center showing two OMNIMAX features, Voyage to the Outer
Planets (produced by Graphic Films) and Garden Isle (by Roger Tilton
Films) on a double bill.
IMAX has since renamed the system IMAX Dome. Many theaters continue
to call it OMNIMAX.
OMNIMAX theaters are now in place at a number of major American
museums, particularly those with a scientific focus, where the
technical aspects of the system may be highlighted as part of the
theme interest. The projection room is often windowed to allow
public viewing and accompanied by informational placards like any
exhibit. Inside the theatre, the screen may be a permanent fixture,
such as at the St. Louis Science Center (which also plays a short
educational video about the OMNIMAX system just before the feature
film); or lowered and raised as needed, such as at the Science
Museum of Minnesota (where it shares an auditorium with a standard
IMAX screen). Before the feature begins, the screen is backlit to
show the speakers and girders behind the screen. IMAX Dome screens
may also be found at several major theme parks.
But despite their impressive capabilities and unique experience, the
system seems likely to remain a novelty rather than a widespread
commercial phenomenon. Relative to their size, OMNIMAX theaters are
very expensive to build and maintain, and have a relatively small
seating capacity. To make matters worse, only those seats closest to
the center of the theater provide the full effect of the immersive
view. Museums are able to run the theaters at a profit only because
they are able to subrogate the construction expenses through grants
and public fundraising and then show relatively inexpensive
documentary films, often while still being able to keep admission
prices lower than those of standard cinemas. In this way, OMNIMAX
theaters have become a "cash cow" for financially strapped public
institutions.
Another use of IMAX Dome technology is to provide an immersive
visual experience to go with a ride simulator, as in Back to the
Future: The Ride. Imax Dome was also used in the former EPCOT
attraction, Horizons.
[edit] IMAX 3D
An IMAX 3D camera.
An IMAX 3D camera.
To create the illusion of 3-dimensional depth, the IMAX 3D process
uses two camera lenses to represent the left and right eyes. The two
lenses are separated by an interoccular distance of about 64 mm/2.5
in., the average distance between a human's eyes. By recording on
two separate rolls of film for the left and right eyes, and then
projecting them simultaneously, we can be tricked into seeing a 3D
image on a 2D screen. The IMAX 3D camera is very cumbersome,
weighing over 113 kg/250 pounds. This makes it extremely difficult
to film on-location documentaries. The IMAX screen, averaging at 8
stories tall, is the perfect medium for 3D movies to be shown on.
Not only does the large negative format allow for pristine quality
images, but the massive screen and close viewing distance provides a
very immersive experience for the audience.
There are two methods to creating the 3D illusion in the theatre.
The first involves polarization. During projection, the left and
right eye images are polarized perpendicular to one another as they
are projected onto the IMAX screen. By wearing special eyeglasses
with lenses polarized in their respective directions to match the
projection, the left eye image can be viewed only by the left eye
since the polarization of the left lens will cancel out that of the
right eye projection, and the right eye image can be viewed only by
the right eye since the polarization of the right lens will cancel
out that of the left eye projection. Another method for 3D
projection involves LCD shutter glasses. These glasses contain LCD
panels which are synchronised to the projector which alternates
rapidly at 96 frames per second between displaying the left and
right images which are momentarily viewed by the appropriate eye by
allowing that eye's panel to become transparent while the other
remains opaque. While the panels within these active-shutter 3D
glasses alternate at 96 frames per second, the actual film is
displayed at 24 frames per second.
One particular problem that 3D movies face is that the 3D effect
does not extend past the boundaries of the physical screen. It is
for this reason that the screen must be large enough to cover as
much of the viewer's peripheral vision as possible. Another problem
with IMAX 3D movies is due to an inherent difference between our
eyes and the film format. Because of the large negative, depth of
field is dramatically reduced, causing an often distracting
depiction of the scene. Computer-generated imagery films do not have
this problem as they are able to control the depth of field in the
images to allow everything to be in focus. While some may argue that
this is less artistic than regular 2D films that purposefully employ
shallow depth of field for aesthetic reasons, the IMAX 3D experience
is a much more immersive one than regular 2D films, and therefore
the viewer can be disoriented by seeing images that are out of focus
– a natural side-effect of the 3D experience.The biggest 3D IMAX
screen is in Prasad's IMAXlocated in Hyderabad ,India[citation
needed]
Improvements in the sound systems have included a 3D sound system
and the elliptical-pattern speaker-clusters.
[edit] IMAX HD
Further improvements and variations on IMAX include the possibility
of a faster 48 frames per second rate, known as IMAX HD.
This system was tested in 1992 at the Canada Pavilion of the Seville
Expo '92 with the film Momentum, but was deemed too costly and
abandoned but not before many theaters were retrofitted to project
at 48 frames, especially Canada.
A theme park in Germany also used IMAX HD for their theme park ride
film in the mid 1990's. Soarin' Over California, originally built at
Disney's California Adventure before being replicated at Epcot,
features a modification of both IMAX HD and IMAX Dome, projecting in
48 frames per second.
[edit] Viewer experience
For the viewer, these technical differences result in a much more
immersive, engaging experience than conventional film projection.
The large screen and close seating mean that much of the viewer's
field of vision is filled with the image, and the high resolution
and positional stability of the film format imparts a sense of
reality and detail. IMAX film can be overwhelming at times, with
some viewers experiencing motion sickness during scenes with
significant motion, especially if the action cuts between moving and
still scenes. In scenes where the motion on the screen moves
downwards, a "free-fall" sensation is felt (like going down on a
roller coaster).
[edit] Recent News
Over the summer of 2006, IMAX's stock fell markedly (by as much as
60%) with the announcement of an SEC investigation[2], falling again
when the announced third quarter earnings were behind the previous
year's. More recently, IMAX delayed fourth quarter filings while
investigating prior accounting errors, first to the end of March and
then as late as the next quarter. Despite these difficulties, IMAX
is expanding its market with several new theaters (especially in
Latin America and China) and has posted record breaking profits from
the recent films Happy Feet, Night at the Museum and 300. For these
reasons, many analysts (including Motley Fool) rate IMAX as a strong
buy during the peak-movie summer season. Analysts expect it to
regain some if not most of the loss suffered in 2006 within summer
2007 with the International premieres of Harry Potter and the Order
of the Phoenix, Pirates of the Caribbean: At World's End, Shrek the
Third, Spider-Man 3 and many other popular venues which have yet to
be announced.
[edit] Content
Although IMAX is an impressive format from a technical perspective,
its popularity as a motion picture format has traditionally been
limited. The expense and logistics of producing and presenting IMAX
films has dictated a shorter running time compared to conventional
movies for most presentations (typically around 40 minutes). The
majority of films in this format tend to be documentaries ideally
suited for institutional venues such as museums and science centers.
IMAX cameras have been taken into space aboard the Space Shuttle, to
Mount Everest, to the bottom of the Atlantic ocean, and to the
Antarctic to film such documentaries. Although IMAX documentaries
have been praised for their technical quality, critics have also
complained that many have banal narration.[citation needed]
Some IMAX theaters had shown conventional films (using conventional
projection equipment) as a sideline to the native-IMAX
presentations. In the late 1990s there was a wave of interest in
broadening the use of IMAX as an entertainment format. A few
pure-entertainment IMAX short films have been created, notably
T-Rex: Back to the Cretaceous, which had a successful run in 1998
and Haunted Castle, released in 2001 (both of these were IMAX 3-D
films). In 1999, The Old Man and the Sea became the first
fully-animated film to be released on IMAX screens and proceeded to
win an Oscar. The same year, Disney produced Fantasia 2000, the
first full-length animated feature released exclusively in the IMAX
format (the film would later have a conventional-theatrical
release). Disney would also release the first 2-D live-action native
IMAX entertainment film, Young Black Stallion, in late 2003.
In the fall of 2002, IMAX and Universal Studios released a new
IMAX-format of the 1995 theatrical film Apollo 13. This release
marked the first use of the IMAX-proprietary "DMR" (Digital
Re-mastering) process that allowed conventional films to be "up"
converted into IMAX format. Other theatrically-released films, would
subsequently be re-released at IMAX venues using the DMR process.
Because of a technical limitation on the size of the film reel,
these early DMR releases were edited to conform to a two-hour length
limitation. Later releases did not have this limitation. Current
IMAX platters allow a run length of up to 150 minutes. It was
previously reported that Star Wars Episode III was released with an
IMAX DMR version, however it never underwent the DMR process. Venues
that showed this film in an IMAX screen used standard 35 mm
projection.
In 2003 a notable IMAX re-release, again using the DMR process, was
The Matrix Reloaded. Later in 2003, the sequel The Matrix
Revolutions was the first live action film to be released
simultaneously in IMAX and conventional theaters, the first feature
film being Treasure Planet.
Reviewers have generally praised the results of the DMR blowup
process, which have superior visual and auditory impact to the same
films projected in 35 mm. Many large format film industry
professionals point out, however, that DMR blowups are not
comparable to films created directly in the 70 mm 15-perf IMAX
format. They note that the decline of Cinerama coincided roughly
with the supersession of the original process with a simplified,
reduced-cost, technically inferior version, and view DMR with alarm.
IMAX originally reserved the phrase "the IMAX experience" for true
70 mm productions, but now allows its use on DMR productions as
well. However, IMAX DMR versions of commercial Hollywood films are
generally popular with audiences, with many people choosing to pay
more than standard admission to see the IMAX version.
Since 2002 many other Hollywood films have been remastered for IMAX.
Warner Brothers has especially embraced the format with the
aforementioned Matrix sequels and since 2004 has been releasing its
Harry Potter film franchise in IMAX to strong financial success. In
2005 WB also released Batman Begins simultaneously in IMAX, which
buoyed the film's strong legs helping it reach $200 m at the
domestic box office, and before the fourth Harry Potter film was
released in IMAX format in November had claimed the record for most
box office by a DMR movie. In summer 2006 WB released the highly
anticipated Superman Returns remastered for IMAX and partially
digitally transformed into 3D (director Bryan Singer chose four
action scenes in the film to show in 3D). The film was a
disappointment at the box office in light of its huge budget and
perceived large fanbase, but the IMAX 3D release helped it to have
strong staying power throughout the summer movie season. Most
recently, WB released the animated film Happy Feet simultaneously in
both conventional theatres and in IMAX 2D format. The studio has
hinted that a future IMAX 3D release was still a possibility.[3]
Noted feature film director James Cameron filmed a movie about the
Titanic in 3D IMAX format, Ghosts of the Abyss.
Up to 2002, eight IMAX format films have received Academy Awards
nomination with one win, the animated short, The Old Man and the Sea
in 2000.
Many IMAX films have been remastered into HDTV format for the INHD
channels.
The movie 300 was released to conventional theaters and to IMAX on
March 9, 2007.
Harry Potter and the Order of the Phoenix will be opening in IMAX on
July 11,2007 with a 20 Minute finale in IMAX 3D.[citation needed]
Director Christopher Nolan has just revealed that 4 scenes,
including the sequence introducing Heath Ledger as The Joker, from
his upcoming Batman Begins sequel, The Dark Knight, will be filmed
in IMAX.[4]
[edit] IMAX as a music venue
In July 2005 the BFI IMAX Cinema in London became the first to host
live music concerts. IMAX theater owners increasingly look to use
the venue at varying times for alternatives to films.
Recently the Science Museum London and the BFI IMAX have hosted
computer game festivals using digital projectors on the large IMAX
screen.
Irish rock band U2 is planning an IMAX 3D movie, U2 3D to be
released in autumn 2007.
These uses have no particular relevance to IMAX as a product or a
company.
[edit] Technical specifications
IMAX (15/70)
* spherical lenses
* 70 mm film, 15 perforations per frame
* horizontal pulldown, from right to left (viewed from base side)
* 24 frames per second
* camera aperture: 70.41 mm (2.772″) by 52.63 mm (2.072″)
* projection aperture: at least 20.3 mm (0.80″) less than camera
aperture on the vertical axis and at least 0.016″ less on the
horizontal axis
* aspect ratio: 1.34:1
IMAX Dome/OMNIMAX
Same as IMAX except:
* special fisheye lenses
* lens optically centered 9.4 mm (0.37″) above film horizontal
center line
* projected elliptically on a dome screen, 20 degrees below and 110
degrees above perfectly centered viewers
[edit] IMAX venues
The Luxor IMAX Theater in the Luxor Hotel is the big black shape.
The Luxor IMAX Theater in the Luxor Hotel is the big black shape.
Main article: List of IMAX venues
Notable IMAX venues include:
* The Cinesphere at Ontario Place in Toronto, Ontario, Canada – the
first permanent IMAX theatre.
* IMAX in Canada Place in Vancouver, British Columbia, Canada – the
first IMAX 3D theatre.
* Futuroscope, France – theme park, only place containing all
versions of IMAX theatres. (Normal, Dome, 3D, 3D Dome ("Solido") and
IMAX Magic Carpet.)
* The Reuben H. Fleet Science Center in San Diego, California, USA –
the first IMAX Dome installation.
* IMAX Wadala, Mumbai - the largest IMAX dome theatre in the world.
* LG IMAX, Sydney, Australia, the largest cinema screen in the
world.[1]
* IMAX Cyber Cafe & Franchise, Malaysia - the largest IMAX cyber
Franchisor in Malysia.Total 13 outlets in 2007.
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