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==IMAX venues==
==IMAX venues==
{{Main|List of IMAX venues}}
{{Main|List of IMAX venues}}

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Revision as of 01:37, 4 January 2010

"i-Max" redirects here. For the Ford Motor Company sports utility vehicle, see Mazda Premacy.

IMAX is a motion picture film format and projection standard created by Canada's IMAX Corporation. The traditional version of IMAX has the capacity to record and display images of far greater size and resolution than conventional film systems. A standard IMAX screen is 22 metres (72 ft) wide and 16.1 metres (53 ft) high, but can vary. The world's largest cinema screen and IMAX screen is in the LG IMAX theatre in Darling Harbour, Sydney. It is 35.73 m wide by 29.42 m (approximately 8 stories) high – covering an area of more than 1,015 square metres.[1]

IMAX is the most widely used system for large-format, special-venue film presentations. As of April 2009, there are 320 IMAX theatres in 42 countries, with about half of these located in the United States. About 60% of IMAX venues are commercial theatres with the other 40% being located in educational venues.[citation needed]

Variations of the traditional IMAX format include IMAX Dome (using a tilted dome screen) formerly called OmniMAX, IMAX 3D and IMAX Digital. Also available is IMAX MPX Theatre System, which defines standards for the conversion of a standard multiplex theater into an IMAX theater.[2]

History

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, but it quickly fell from use. In the 1950s, CinemaScope (introduced in 1953) and VistaVision (1954) widened the image projected from 35 mm film, and there were multi-projector systems such as Cinerama (1952) for even wider presentations. While impressive, Cinerama was difficult to set up, and the seams between adjacent projected images were difficult to hide.

The IMAX system was developed by Graeme Ferguson, Roman Kroitor, Robert Kerr, and William C. Shaw. [3]

During Expo 67 in Montreal, Kroitor's In the Labyrinth, and Ferguson's "Man and The Polar Regions", both used multi-projector, multi-screen systems. Each encountered a number of technical difficulties that led them to found a company, initially called "Multiscreen", with a primary goal of designing and developing a simpler approach. The single-projector/single-camera system they eventually settled upon was designed and built by Shaw, based upon novel "Rolling Loop" film-transport technology purchased from the Australian inventor Ronald Jones. Later, when it became clear that a single, large-screen image had far more impact than multiple smaller ones, Multiscreen changed its name to IMAX.

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 × 65 ft (27.3 × 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 was in use until September 30, 2009[4]. It was located at the tip of Canada Place, a Vancouver landmark.

Over the summer of 2006, IMAX's stock fell markedly (by as much as 60%) with the announcement of an SEC investigation[5], falling again when the announced third quarter earnings were behind the previous year's.

Technical aspects

A comparison between 35 mm and 15/70 mm negative areas
An IMAX camera inside a display case
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 a much larger film frame. To achieve this, 65 mm film stock is run horizontally through the cameras. While traditional 65 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 586× 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 four registration pins engage the sprockets at the corners of the projected frame to ensure perfect alignment. 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. An IMAX projector is therefore a substantial piece of equipment, weighing up to 1.8 tonnes and towering at over 178 centimetres (70 in) tall and 195 centimetres (77 in) long. The xenon lamps are made of a thin layer of quartz crystal, and contain xenon gas at a pressure of about 25 atmospheres (367 PSI); because of this, projectionists are required to wear protective body armor when changing or handling these in case the lamp breaks (e.g., due to a drop to the floor) because the flying shards of crystal could be deadly when combined with the high pressure of the gas within.[citation needed]

IMAX uses a stronger "ESTAR" (Kodak's trade name 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 (especially 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 sprocket holes per frame of 70 mm stock. The bulk of the film requires large platters rather than conventional film reels.[citation needed]

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 film synchronized to the film. (This original "mag-stripe" system was commonly used to "dub" or insert studio sound into the mixed soundtrack of conventional films.) By the early 1990s, a separate digital 6-track source was synchronized using a more precise pulse generator as a source for a conventional SMPTE time code synchronization system. This development presaged conventional 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. Many IMAX theaters place speakers directly behind the screen, as well as distributing the speakers around the theater to create a three-dimensional effect.[citation needed]

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.[citation needed]

IMAX variations

IMAX 3D

To create the illusion of three-dimensional depth, the IMAX 3D process uses two camera lenses to represent the left and right eyes. The two lenses are separated by an interocular distance of 64 mm (2.5"), 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, viewers can be tricked into seeing a 3D image on a 2D screen. The IMAX 3D camera is cumbersome, weighing over 113 kg (250 lb). This makes it difficult to film on-location documentaries.

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 linearly polarized perpendicular to one another (or right-hand and left-hand circular polarization is used) 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.

Several films produced in the RealD 3D process for release in conventional theaters have also been presented in IMAX 3D, including Dreamworks' Monsters vs Aliens, Columbia Pictures' The Little Engine That Could, U2 3D and Avatar.

IMAX HD (48 fps)

Variations on IMAX included the 48 frames per second IMAX HD process, which sought to reduce strobing and offer a more high definition image by filming and projecting at twice the normal film rate.

History

The IMAX HD system was tested in 1992 at the Canada Pavilion of the Seville Expo '92 with the film Momentum. It was deemed too costly and abandoned but not before many theaters were retrofitted to project at 48 frames, especially in Canada.[citation needed] A theme park in Germany also used IMAX HD for a film in the mid-1990s.[citation needed] The Disney parks attraction Soarin' Over California features a modification of both IMAX HD and IMAX Dome, projecting in 48 frames per second.

Production issues

The doubled IMAX HD frame rate means that each IMAX HD reel lasts half as long, and the logistical implications of this reach all the way up the film production chain. IMAX production by default is at least 3 to 5 times more expensive against common 70mm production. The increased production costs make IMAX HD problematic regardless of overall production funding issues, and the format has not seen significant adoption.

IMAX Digital

A digital version of IMAX started rolling out in 2008. The new system is a projection standard only; there are no digital IMAX cameras.[citation needed]

Digital IMAX systems can show either normal or 3D content in DCI or IMAX digital format (which in itself is a superset of DCI). The digital system alleviates the need for the use of bulky film reels and facilitates inexpensive distribution of IMAX features, the more compact nature of digital equipment means the system can fit inside a normal multiplex cinema complex rather than the specialised buildings IMAX normally requires.[citation needed]

Despite those advantages, one big disadvantage is the resolution of the picture is much lower than normal IMAX. The screens used by digital IMAX installations are also much smaller (28×58 feet) than those found in traditional IMAX cinemas. The digital installations have drawn some confusion based on poor consumer differentiation to the traditional 15/70 IMAX.[6]

Deals have already been signed with Hollywood studios for IMAX 3D features, such as "Shrek Forever After 3D".[7]

IMAX digital currently uses two 2K-resolution Christie projectors with Texas Instruments Digital Light Processing technology alongside parts of IMAX's proprietary system. The two 2K images are projected over each other, producing an image that is potentially of a slightly higher resolution than common 2K digital cinema. Originally, IMAX had been considering using two Sony 4K projectors.[8] Some reviewers note that this approach may not produce image quality higher than using one 4K projector, which are available for some non-IMAX theaters,[6] including AMC's own. [9]

IMAX recently signed a deal with AMC to start utilizing IMAX digital beginning July 2008 in the US. In December 2008 two digital screens were opened inside Odeon Cinemas in the UK[10] and three inside Hoyts Cinemas in Australia with a fourth to follow later in 2009[11].

Digital Backlash

IMAX Corporation's decision not to designate the new digital installations in any manner has led to a backlash by some viewers who are disappointed to have paid a premium to view an IMAX presentation only to find it being shown with much lower resolution on a screen of relatively ordinary size.[12] Some reviewers have pointed out that the visual artifacts due to low resolution are detrimental to the picture quality, especially for viewers seated closer to the screen.[6] The company CEO has stated that in digital IMAX installations the last few rows of seats are removed, allowing the screen to be closer to moviegoers, which makes the screen appear larger than it would in a standard theater setting.[13]

Content

The use of the IMAX format has traditionally been limited to specialty applications. The expense and logistics of producing and presenting IMAX films has dictated a shorter running time compared to conventional movies for most presentations (typically shorter by about 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. An IMAX documentary about the success of the Mars Exploration Rovers was released in 2006, titled Roving Mars and used exclusive data from the Rovers.

One of the first attempts at presenting an entertainment film in the IMAX format was The Rolling Stones: Live at the Max (1991), an 85-minute compilation of concert footage filmed in IMAX during the band's 1990 tour, edited to give the impression of a single concert.

Later in the 1990s, there was increasing interest in broadening the use of IMAX as an entertainment format. More entertainment IMAX short films were created, notably T-Rex: Back to the Cretaceous (directed by Brett Leonard), which had a successful run in 1998 and Haunted Castle, released in 2001 (both of these were IMAX 3D 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 2D live action native IMAX entertainment film, Young Black Stallion, in late 2003. In 2008, the Rolling Stones concert film, Shine a Light, directed by Martin Scorsese, was released as an IMAX DMR blowup version.

In the fall of 2002, IMAX and Universal Studios released a new IMAX-format version of the 1995 theatrical film Apollo 13. This release marked the first use of the IMAX proprietary "DMR" (Digital Media Remastering) process that allowed conventional films to be upconverted into IMAX format. Other theatrically released films would subsequently be rereleased at IMAX venues in versions created using the DMR process. Because of a technical limitation on the size of the film reel, several early DMR releases were edited to conform to a two-hour maximum length. Later releases did not have this limitation; current IMAX platters allow a run length of up to 165 minutes. Some IMAX theaters have also shown conventional films (using conventional projection equipment) as a sideline to the native IMAX presentations.

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.[citation needed] Many large format film industry professionals[who?] 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 two Matrix sequels, and since 2004 has been releasing its Harry Potter film franchise in IMAX to strong financial success. Also in 2004 the company released the animated movie The Polar Express to IMAX in 3D. Express became the most successful movie ever to be released in IMAX theaters, making at least a quarter of the film total worldwide gross of $302 million from less than 100 IMAX screens; because of its success, it has been re-released each holiday season since. In 2005 WB also released Batman Begins simultaneously in conventional theaters and IMAX, helping the film it reach $200M at the domestic box office. In summer 2006 WB released the highly anticipated Superman Returns remastered for IMAX and partially digitally transformed into 3D (director Bryan Singer chose the only four action scenes in the film to show in 3D). Spider-Man 3 broke the IMAX gross record in 2007 by a huge margin.

The July 2008 Batman Begins sequel The Dark Knight featured six sequences (a total of 30 minutes) shot using IMAX technology, which the movie's press notes describe as the "first time ever that a major feature film has been even partially shot using IMAX cameras".[14] The film broke box office records for IMAX, taking in about $6.3 million from 94 theaters in the U.S. and Canada over the opening weekend. The record for an IMAX opening weekend (as of May 2009) was set by Star Trek: The IMAX Experience, which took in $8.3 million.[1]. The current IMAX opening weekend record (as of December 2009) is held by Titanic director James Cameron's Avatar which brought in $9.5 million.[2].

Awards

Up to 2009, ten native-format IMAX format films have received Academy Awards nomination with one win: the animated short, The Old Man and the Sea. Here is the list of films that were nominated:

  • Dolphins, 2000 Documentary (Short Subject)
  • More, 1998 Short Film (Animated)
  • Alaska: Spirit of the Wild, 1997 Documentary (Short Subject)
  • Amazon, 1997 Documentary (Short Subject)
  • Cosmic Voyage, 1996 Documentary (Short Subject)
  • Special Effects, 1996 Documentary (Short Subject)
  • The Living Sea, 1995 Documentary (Short Subject)
  • Fires of Kuwait, 1992 Documentary (Feature)
  • The Eruption of Mount St. Helens, 1980 Documentary (Short Subject)

Many IMAX films have been remastered into HDTV format for the MOJO HD channel with limited commercial interruption. They can also occasionally be shown commercial free on HDNet and with limited commercials on HD Theater.

Other uses

In July 2005 the BFI IMAX Cinema in London became the first to host live music concerts, using a digital non-IMAX projector. IMAX theatre owners increasingly look to use the venue at varying times for alternatives to films.

The Science Museum London and BFI IMAX Cinema have also hosted computer game tournaments using digital projectors on the large IMAX screen. Other IMAX Theatres have also followed suit with game tournaments on their screens as well.

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: 1.44:1

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

IMAX venues

Main article: List of IMAX venues

See also

References

  1. ^ "Visitor info". IMAX. Retrieved 2009-10-07.
  2. ^ Template:Cite doc
  3. ^ The Birth of IMAX
  4. ^ http://www.imax.com/vancouver/
  5. ^ National Post Story "'Red Flags' at IMAX", Monday, April 09, 2007
  6. ^ a b c Hyder, James (2008-10-16). Is IMAX the next "New Coke"? LF Examiner, 16 October 2008. Retrieved from http://www.lfexaminer.com/20081016.htm.
  7. ^ Local theaters to get new Imax screens - Baltimore Business Journal:
  8. ^ IMAX focuses on DLP chips
  9. ^ http://broadcastengineering.com/hdtv/amc_theatres_sony_projectors/
  10. ^ http://fullres.blogspot.com/2008/06/imax-digital.html IT Broadcast and Digital Cinema blog
  11. ^ IMAX, Hoyts team up in Australia - Variety
  12. ^ Is Digital IMAX Scamming Moviegoers?
  13. ^ Goldstein, Patrick (2009-05-22). Should Imax tell moviegoers the size of its screens? Los Angeles Times, 22 May 2009. Retrieved from http://latimesblogs.latimes.com/the_big_picture/2009/05/should-imax-tell-moviegoers-the-size-of-its-screens.html.
  14. ^ Warner Bros. Pictures press notes, The Dark Knight
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