One of the most important aspects of television viewing but often not taken into account is aspect ratio. You might have spent thousands on rupees on your new television but perhaps have not considered how it would be to watch pictures if they were to appear distorted on the screen. That would be a deterrent in your TV viewing experience.Television screens have basically two native aspect ratios: 16:9 (16x9, 1.78:1, or widescreen) and 4:3 (also known as 4x3, 1.33:1, or standard). The latter is the most common in standard CRT TVs. 16:9 is the aspect ratio of mostHDTVs (high-definition televisions). 16:9 is considered the best because of its ability to show theatre-quality images.

Basics of aspect ratioAspect Ratio refers to the ratio of width to height of your TV screen and is widely used to denote the shape of a TV or computer screen. The two most common aspect ratios we find in televisions are, as stated earlier, 4:3 and 16:9. The aspect ratio of a standard TV screen is 4:3. (which means the ratio of width to height is 4:3) and the other is 16:9 (which means the ratio of width to height is 16:9).

4:3 aspect ratio imagesThis aspect ratio is the most common one, since most of our televisions as well as the broadcast service offer images in 4:3 aspect ratio. The broadcasts, being of 4:3 ratio, fill up the entire space on our TV screens, which is also of 4:3 ratio, and this is why while watching TV you never encounter any viewing problem. The problem arises when you watch 4:3 broadcast or video on the latest widescreen HDTVs available in the market. You can see those black columns on the left and right of your screen when you watch a conventional 4:3 program on your widescreen TV. This phenomenon is called "pillar boxed" picture. Some of you might be fine with viewing images in this pillar boxed form but for those who find it awkward, you can get rid of it by either stretching or zooming with the help of your TV remote so as to fill up the whole screen. Generally, the zoomed images look better than the stretched images.

http://www.filmbug.com/dictionary/aspect-ratios.php

The aspect ratio of an image is its displayed width divided by its height (usually expressed as "x:y").

For instance, the aspect ratio of a traditional television screen is 4:3, or 1.33:1. High definition

television uses an aspect of 16:9, or about 1.78:1. Aspect ratios of 2.35:1 or 1.85:1 are frequently used

in cinematography, while the aspect ratio of a standard 35mm film frame is around 1.37:1.

Comparison of three common aspect ratios.

Comparison of three common aspect ratios. The outer box (blue) and middle box (red) are common formats for

cinematography. The inner box (green) is the format used in standard television.

The outer box (blue) and middle box (red) are common formats for cinematography. The inner box

(green) is the format used in standard television.Within the motion picture industry, the convention is

to assign a value of 1 to the image height, so that, for example, a Cinemascope frame is described as

2.35:1 or just "2.35". This way of speaking comes about because the width of a film image is restricted

by the presence of sprocket holes and, usually, an optical sound track on the projection print.

Development of various camera systems therefore centers on the placement of the frame in relation to

these lateral constraints; the height of image can be adjusted freely, so the ingenuity goes into getting

different widths. One clever widescreen process, VistaVision, used standard 35mm film running

sideways through camera gate, so that the sprocket holes were above and below frame and the width

was not restricted. The most common projection ratios in American theaters are 1.85 and 2.35.

The term is also used in the context of computer graphics to describe the shape of an individual pixel

in a digitized image. Most digital imaging systems use square pixels--that is, they sample an image at

the same resolution horizontally and vertically. But there are some devices that do not, so a digital

image scanned at twice the horizontal resolution to its vertical resolution might be described as being

sampled at a 2:1 aspect ratio, regardless of the size or shape of the image as a whole.

A widescreen image is a film image with a greater aspect ratio than the ordinary 35 millimeter frame.

The aspect ratio of a standard 35 millimeter frame is around 1.37:1, although cameramen may use

only the part of the frame which will be visible on a television screen (which is 1.33:1 for standard

television). Viewfinders are typically inscribed with a number of frame guides, for various ratios.

Note that aspect ratio refers here to the projected image. There are various ways of producing a

widescreen image of any given proportion.

Anamorphic: used by Cinemascope, Panavision and others. Anamorphic camera lenses

compress the image horizontally so that it fits a standard frame, and anamorphic projection

lenses restore the image and spread it over the wide screen. The picture quality is reduced

because the image is stretched to twice the original area, but improvements in film and lenses

have made this less noticeable.

Masked: the film is shot in standard ratio, but the top and bottom of the picture are masked off

by mattes in the projector. Alternatively, a hard matte in the camera may be used to mask off

those areas while filming. Once again the picture quality is reduced because only part of the

image is being expanded to full height. Sometimes films are designed to be shown in cinemas

in masked widescreen format but the full unmasked frame is used for television. A low-budget

movie called Secret File: Hollywood, often ridiculed as a collection of bloopers, is actually an

example of a film that is always projected wrong. All the lights and microphone booms visible

above the actors should be concealed by a projection matte, creating an image that would fill

a wide screen for little money.

Multiple camera/projector: the Cinerama system originally involved shooting with three

synchronized cameras locked together side by side, and projecting the three resulting films on

a curved screen with three synchronized projectors. Later Cinerama movies were shot in super

anamorphic (see below), and the resultant widescreen image was divided into three by optical

printer lenses to produce the final threefold prints. The technical drawbacks of Cinerama are

discussed in its own article.

Big film format: a 70mm film frame is not only twice as wide as a standard frame but also has

greater height. Shooting and projecting a film in 70mm therefore gives more than twice the

image area of non-anamorphic 35mm film with no loss of quality.

Super anamorphic: 70mm with anamorphic lenses creates an even wider high-quality picture.

Letterboxing is the practice of copying widescreen film to video formats while preserving the original

aspect ratio. Since the video display is most often a more square aspect ratio than the original film, the

resulting master must include masked-off areas above and below the picture area (these are often

referred to as "black bars", resembling a letterbox slot). The term takes its name from the similarity of

the resulting image to a horizontal opening in a postal letter box. The resulting video master utilizes

only a portion of the display screen, the technique offers an alternative to the older pan and scan

method of copying that cropped the image to suit the 4:3 (or 12:9) ratio of the television screen and

preserves the original composition of the film as seen in the theater.

Some filmmakers state a preference for letterboxed videos of their work. Woody Allen's insistence on a

letterboxed release of Manhattan probably inspired this treatment of other films. One exception to the

preference is Milos Forman, who finds the bands distracting. However, most video releases are made

without consultation with either the director or director of cinematography of the film. The letterboxing

is often careless, and the common 16:9 ratio does not precisely correspond to aspect ratios of the

most common widescreen systems.

HDTV, a newer digital video system, uses video displays with a wider aspect ratio than standard

television and, is becoming the broadcast standard in the United States. The wider screen will make it

easier to make an accurate letterbox transfer. Some contemporary television programming is being

produced in letterbox format. This is done both to give a "classier" look to the image (particularly in

the case of advertising), and to facilitate the production of widescreen programming for later

syndication in HDTV.

16:9 widescreen television is also becoming common on European digital television systems. Although

this is not true HDTV it uses the same aspect ratio, and the majority of programming in countries like

Britain and France is now made in letterbox format. Of course, on a true widescreen television set the

"letterboxed" 16:9 picture is no longer letterboxed since it fills the entire screen. However, movies

made in even wider aspect ratios are letterboxed to some extent even on 16:9 sets.

Sometimes, by accident or design, a standard-ratio image is presented in the central portion of a

letterboxed picture, resulting in a black border all around. This is referred to as "matchboxing" and is

generally disliked because it wastes a lot of screen space and reduces the resolution of the original

image. This can for instance be seen on some of the DVD editions of the Star Trek movies whenever

the widescreen documentaries included as extras use footage from the original TV series. The

alternative would be to crop the original 4:3 TV images horizontally to fit the 16:9 ratio.

Pan and scan is a method of adjusting widescreen film images so that they can be shown within the

proportions of an ordinary video screen.

Until High Definition Television came onto the scene, television images had approximately the shape

of a frame of 35mm film: a width 1.33 times the height (in the industry, referred to as "4:3 aspect

ratio"). By contrast, a film image typically has a more rectangular final projected image with an aspect

ratio greater than 16:9, often as wide as 2.35 times the height of the image. To broadcast a

widescreen film on television, or create a videotape or DVD master it is necessary to make a new

version from the original filmed elements. One way to do so is to make a "letterbox" print, which

preserves the original theatrical aspect ratio, but produces an image with black bars at the top and

bottom of the screen. Another way to turn the 16:9 aspect ratio film into a 4:3 aspect ratio television

image is to "pan and scan" the negative.

During the "pan and scan" process, an operator selects the parts of the original filmed composition

that seem to be significant and makes sure they are copied—"scanning." When the important action

shifts to a new position in the frame, the operator moves the scanner to follow it, creating the effect of

a pan shot.

This method allows the maximum resolution of the image, since it uses all the available video scan

lines. It also gives a full-screen image on analog television. But it can also severely alter compositions

and therefore dramatic effects—for instance, in the film Jaws, the shark can be seen approaching for

several seconds more in the widescreen version than in the pan and scan version. In some cases, the

results can also be a bit jarring, especially in shots with significant detail on both sides of the frame:

the operator must either go to a two-shot format (alternating between closeups in what was previously

a single image), lose some of the image, or make several abrupt pans. In cases where a film director

has carefully designed his composition for optimal viewing on a wide theatrical screen, these changes

may be seen as changing that director's vision to an unacceptable extent.

Once television revenues became important to the success of theatrical films, cameramen began to

work for compositions that would keep the vital information within the "TV safe area" of the frame. For

example, the BBC suggests program producers frame their shots in a 14:9 aspect ratio to minimize the

effects of converting film to television. In other cases film directors reverse this process, creating a

negative with information that extends above and below the widescreen theatrical image (this is

sometimes referred to as a "full frame" composition). Often pan-and-scan compositors make use of

this full-screen negative as a starting point, so that in some scenes the TV version may contain more

image content than the widescreen version while in other scenes where such an "opened" composition

is not appropriate a subset of the widescreen image may be selected. In some cases (notably many of

the films of Stanley Kubrick) the original 1.33:1 aspect ratio of the negative is transferred directly to

the video master (although these versions also represent a new aspect ratio compared to the original

theatrical release these are not properly "pan and scan" transfers at all but are often called "full-

frame" or "open matte" transfers).

Yet some directors still balk at the use of "pan and scan" version of their movies; for instance Steven

Spielberg initially refused to release a pan and scan version of Raiders of the Lost Ark, but eventually

gave in; Woody Allen refused altogether to release one of Manhattan and the letterboxed version is in

fact the only version available on VHS and DVD.

Cinemascope, or more strictly CinemaScope, was a widescreen movie format used in the US from 1953

to 1967. Using anamorphic lenses and 35 mm film it could project film at a 2.66:1 ratio, twice as wide

as conventional lenses could achieve.

It was developed by 20th Century Fox to supplant the complex, multi-projector Cinerama process, first

shown in 1952. The actual anamorphic process, initially called Anamorphoscope, was developed by

Henri Chétien around 1927 using lenses he called hypergonar. Chétien had been attempting to sell his

process to Hollywood since the 1930s but with little interest, until the advent of Cinerama. Another

factor was the rise of television, which meant that the studios saw the need for a spectacle to

compete.

The hypergonar lens patents were acquired by 20th Century Fox in 1952 and the system was renamed

Fox CinemaScope. The advantage over Cinerama was that all the system needed was an additional

lens unit fitted to the front of ordinary cameras and projectors, although stereo sound could be carried

on separate 35mm tracks. It was first demonstrated in 1953 and the first film shot was The Robe

(September 1953). The technology was licensed by Fox to MGM and Disney and shortly afterwards to

Columbia, Universal and Warner. However, initial uncertainty meant that a number of films were shot

simultaneously with anamorphic and regular lenses. Also only the 'biggest' films were made in

Cinemascope, around a third of the total produced.

Although Cinemascope was capable of producing a 2.66:1 image, the addition of stereo information

could reduce this to 2.55:1. A change in the base 35 mm film aperture eventually reduced

Cinemascope to 2.35:1. Often cinemas with smaller screens would further crop the format to make it

fit. A general problem with expanding the visible image meant that there could be visible grainyness

and brightness problems, so to combat this larger formats were developed; initially an unsuccessful 55

mm, and later 65 and 70 mm.

Since the actual anamorphic process was not patentable (it had been known for centuries and had

been used in paintings such as "The Ambassadors" by Hans Holbein), some studios sought to develop

their own systems rather than pay Fox - RKO used Superscope, Republic used Naturama, Warner

developed Warnerscope. Other systems developed included Panatar, Vistarama, Technovision and

Euroscope. Cinemascope itself was called Regalscope when used by the Fox adjunct Regal Films for

black-and-white features.

Many US studios adopted the cheaper, non-Fox, but still anamorphic Panavision system and by the

mid-1960s even Fox had abandoned Cinemascope for Panavision. The initial problems with grain and

contrast were eventually solved thanks to improvements in film stock and lenses.

http://en.wikipedia.org/wiki/Aspect_ratio_(image)

The aspect ratio of an image describes the proportional relationship between its width and its height.

It is commonly expressed as two numbers separated by a colon, as in 16:9. For an x:y aspect ratio, no

matter how big or small the image is, if the width is divided into x units of equal length and the height is

measured using this same length unit, the height will be measured to be y units. For example, consider a

group of images, all with an aspect ratio of 16:9. One image is 16 inches wide and 9 inches high. Another

image is 16 centimeters wide and 9 centimeters high. A third is 8 yards wide and 4.5 yards high.

The most common aspect ratios used today in the presentation of films in movie theaters

are 1.85:1 and 2.39:1.[1] Two common videographic aspect ratios are 4:3 (1.33:1), the universal video

format of the 20th century and 16:9 (1.77:1), universal for high-definition television and European digital

television. Other cinema and video aspect ratios exist, but are used infrequently.

In still camera photography, the most common aspect ratios are 4:3, 3:2, and more recently being found

in consumer cameras 16:9.[2] Other aspect ratios, such as 5:3, 5:4, and 1:1 (square format), are used in

photography as well, particularly in medium format and large format.

With television, DVD and Blu-ray Disc, converting formats of unequal ratios is achieved by enlarging the

original image to fill the receiving format's display area and cutting off any excess picture information

(zooming and cropping), by adding horizontal mattes (letterboxing) or vertical mattes (pillarboxing) to

retain the original format's aspect ratio, by stretching (hence distorting) the image to fill the receiving

format's ratio, or by scaling by different factors in both directions, possibly scaling by a different factor in

the center and at the edges (as in Wide Zoom mode).

[edit]Practical limitations

In motion picture formats, the physical size of the film area between the sprocket perforations determines

the image's size. The universal standard (established by William Dickson and Thomas Edison in 1892) is

a frame that is four perforations high. The film itself is 35 mm wide (1.38 in), but the area between the

perforations is 24.89 mm×18.67 mm (0.980 in×0.735 in), leaving the de facto ratio of 4:3, or 1.33:1.[3] A

4:3 ratio mimics human eyesight visual angle of 155°h x 120°v, that is 4:3.075, almost exactly the same.

With a space designated for the standard optical soundtrack, and the frame size reduced to maintain an

image that is wider than tall, this resulted in the Academy aperture of 22 mm × 16 mm (0.866 in ×

0.630 in) or 1.37:1 aspect ratio.

[edit]Cinema terminology

The motion picture industry convention assigns a value of 1.0 to the image’s height; thus,

an anamorphic frame (actually 2.39:1) is described (rounded) as 2.40:1 or 2.40 ("two-four-oh"). In

American cinemas, the common projection ratios are 1.85:1 and 2.40:1. Some European countries have

1.66:1 as the wide screen standard. The "Academy ratio" of 1.37:1 was used for all cinema films until

1953 (with the release of George Stevens's Shane in 1.66:1). During that time, television, which had a

similar aspect ratio of 1.33:1, became a threat to movie audiences, Hollywood gave birth to a large

number of wide-screen formats: CinemaScope (up to 2.66:1), Todd-AO (2.20:1), and VistaVision (initially

1.50:1, now 1.66:1 to 2.00:1) to name just a few. The "flat" 1.85:1 aspect ratio was introduced in May,

1953, and became one of the most common cinema projection standards in the U.S. and elsewhere.

[edit]Movie camera systems

Development of various film camera systems must ultimately cater to the placement of the frame in

relation to the lateral constraints of the perforations and the optical soundtrack area. One clever wide

screen alternative, VistaVision, used standard 35 mm film running sideways through the camera gate, so

that the sprocket holes were above and below frame, allowing a larger horizontal negative size per frame

as only the vertical size was now restricted by the perforations. However, the 1.50:1 ratio of the initial

VistaVision image was optically converted to a vertical print (on standard 4-perforation 35 mm film) to

show in the projectors available at theaters, and was then masked in the projector to the US standard of

1.85:1. The format was briefly revived by Lucasfilm in the 1970s for special effects work that required

larger negative size (due to image degradation from the optical printing steps necessary to make multi-

layer composites). It went into obsolescence largely due to better cameras, lenses, and film stocks

available to standard 4-perforation formats, in addition to increased lab costs of making prints in

comparison to more standard vertical processes. (The horizontal process was later adapted to 70 mm film

by IMAX.)

Super 16 mm film is frequently used for television production due to its lower cost, lack of need for

soundtrack space on the film itself (as it is not projected but rather transferred to video), and aspect ratio

similar to 16:9 (the native ratio of Super 16 mm is 15:9). It also can be blown up to 35 mm for theatrical

release and therefore is sometimes used for feature films.

[edit]Current video standards

[edit]4:3 standard

4:3 (1.33:1) (generally read as "Four-Three", "Four-by-Three", or "Four-to-Three") for standard television

has been in use since the invention of moving picture cameras and many computer monitors employ the

same aspect ratio. 4:3 was the aspect ratio used for 35 mm films in the silent era and is used today for

film production under the name Super 35. It is also very close to the 1.375:1 aspect ratio defined by

the Academy of Motion Picture Arts and Sciences as a standard after the advent of optical sound-on-film.

By having TV match this aspect ratio, movies originally photographed on 35 mm film could be

satisfactorily viewed on TV in the early days of the medium (i.e. the 1940s and the 1950s).

When cinema attendance dropped, Hollywood created widescreenaspect ratios (such as the 1.85:1 ratio

mentioned earlier) in order to differentiate the film industry from TV.

[edit]16:9 standard

Main article: 16:9

16:9 (1.77:1) (generally named as "Sixteen-Nine", "Sixteen-by-Nine" and "Sixteen-to-Nine") is the

international standard format of HDTV, non-HD digital television and analog widescreen

televisionPALplus. Japan's Hi-Vision originally started with a 5:3 ratio but converted when the

international standards group introduced a wider ratio of 5⅓ to 3 (=16:9). Many digital video cameras

have the capability to record in 16:9, and 16:9 is the only widescreen aspect ratio natively supported by

the DVD standard. DVD producers can also choose to show even wider ratios such as 1.85:1 and

2.39:1[1] within the 16:9 DVD frame by hard matting or adding black bars within the image itself. Some

films which were made in a 1.85:1 aspect ratio, such as the U.S.-Italian co-production Man of La Mancha,

fit quite comfortably onto a 1.77:1 HDTV screen and have been issued anamorphically enhanced on DVD

without the black bars.

[edit]Obtaining height, width and area of the screen

Often, screen specifications are given by their diagonal length. The following formulae can be used to find

the height (h), width (l for length) and area (A), where r stands for ratio and d for diagonal length.

[edit]Distinctions

Further information: Pixel aspect ratio

This article primarily addresses the aspect ratio of images as displayed, which is more formally referred to

as the Display Aspect Ratio (DAR). In digital images, there is a distinction with theStorage Aspect

Ratio (SAR), which is the ratio of pixel dimensions. If an image is displayed with square pixels, then these

ratios agree; if not, then non-square, "rectangular" pixels are used, and these ratios disagree. The aspect

ratio of the pixels themselves is known as the Pixel Aspect Ratio (PAR) – for square pixels this is 1:1 –

and these are related by the identity:

SAR × PAR = DAR.

Rearranging (solving for PAR) yields:

PAR = DAR/SAR.

For example, a 640 × 480 VGA image has a SAR of 640/480 = 4:3, and if displayed on a 4:3

display (DAR = 4:3) has square pixels, hence a PAR of 1:1. By contrast, a 720 × 576 D-1 PAL

image has a SAR of 720/576 = 5:4, but is displayed on a 4:3 display (DAR = 4:3), so by this

formula it would have a PAR of (4:3)/(5:4) = 16:15.

However, because standard definition digital video was originally based on digitally sampling

analog television, the 720 horizontal pixels actually capture a slightly wider image to avoid loss of

the original analog picture. In actual images, these extra pixels are often partly or entirely black,

as only the center 704 horizontal pixels carry actual 4:3 or 16:9 image. Hence, the actual pixel

aspect ratio for PAL video is a little different from that given by the formula, specifically 12:11 for

PAL and 10:11 for NTSC. For consistency, the same effective pixel aspect ratios are used even

for standard definition digital video originated in digital form rather than converted from analog.

For more details refer to the main article.

In analog images such as film there is no notion of pixel, nor notion of SAR or PAR, and "aspect

ratio" refers unambiguously to DAR. Actual displays do not generally have non-square pixels,

though digital sensors might; they are rather a mathematical abstraction used in resampling

images to convert between resolutions.

Non-square pixels arise often in early digital TV standards, related to digitalization of analog TV

signals – whose horizontal and vertical resolutions differ and are thus best described by non-

square pixels – and also in some digital videocameras and computer display modes, such

as Color Graphics Adapter (CGA). Today they arise particularly in transcoding between

resolutions with different SARs.

DAR is also known as Image Aspect Ratio and Picture Aspect Ratio, though the latter can be

confused with Pixel Aspect Ratio.

[edit]Visual comparisons

Comparing two different aspect ratios poses some subtleties – when comparing two aspect

ratios, one may compare images with equal height, equal width, equal diagonal, or equal area.

More amorphous questions include whether particular subject matter has a natural aspect ratio

(panoramas being wide, full-length images of people being tall), or whether a particular ratio is

more or less aesthetically pleasing – the golden ratio (~1.618) is seen as especially pleasing. Of

common display formats, 16:10 is the closest to the golden ratio, and 15:9 is the closest film

format.

Given the same diagonal, the 4:3 screen offers more (over 12%) area, because it is closer to

square (which maximizes area given a diagonal). For CRT-based technology, an aspect ratio

that is closer to square is cheaper to manufacture. The same is true for projectors, and other

optical devices such as cameras, camcorders, etc. For LCD and Plasma displays, however, the

cost is more related to the area, so producing wider and shorter screens yields the same

advertised diagonal but lower area, and hence is more profitable.

The following compares crops of a given image at 4:3 and 16:9, with different parameters equal;

note that in terms of subject, the squarer aspect ratio emphasizes the public square, while the

wider aspect ratio emphasizes the wide building.

Two aspect ratios compared with images using the same diagonal size:

4:3 (1.33:1)

16:9 (1.77:1)

Two aspect ratios compared with images using the same area (number of pixels):

4:3 (1.33:1)16:9 (1.77:1)

Two aspect ratios compared with images using the same height (vertical size):

4:3 (1.33:1) 16:9 (1.77:1)

Two aspect ratios compared with images using the same width (horizontal size):

4:3 (1.33:1)

16:9 (1.77:1)

[edit]Previous and currently used aspect ratios

See list of common resolutions for a listing of computer resolutions and aspect ratios.

See list of film formats for a full listing of film formats, including their aspect ratios.

Comparison between several film aspect ratios with the heights forced to be equal.

1.15:1 Sometimes referred to as the Movietone ratio, this ratio was used briefly

during the transitional period when the film industry was converting to sound, from

1926 to 1932 approx. It is produced by superimposing an optical soundtrack over a

full-gate 1.33 aperture in printing, resulting in an almost square image. Films shot in

this ratio are often projected or transferred to video incorrectly using a 1.37 mask.

Examples of films shot in the Movietone ratio include Sunrise, M and Hallelujah!.[4]

1.33:1 (4:3, 12:9): 35 mm original silent film ratio, today commonly known in TV

and video as 4:3. Also standard ratio for MPEG-2 video compression. This format is

still used in many personal video cameras today and has influenced the selection or

design of other aspect ratios. It is the standard 16 mm and Super 35mm ratio.

1.37:1: 35 mm full-screen sound film image, nearly universal in movies between

1932 and 1953. Officially adopted as the Academy ratio in 1932 by AMPAS. Rarely

used in theatrical context nowadays, but occasionally used for other context.

1.44:1: IMAX format. Imax productions use 70 mm wide film (the same as used for

70 mm feature films), but the film runs through the camera and projector

horizontally. This allows for a physically larger area for each image.

1.50:1 (3:2, 15:10): The aspect ratio of 35 mm film used for still photography when 8

perforations are exposed. Also the native aspect ratio of VistaVision, for which the

film runs horizontally.

1.55:1 (14:9): Widescreen aspect ratio sometimes used in shooting commercials

etc. as a compromise format between 4:3 (12:9) and 16:9. When converted to a

16:9 frame, there is slight pillarboxing, while conversion to 4:3 creates

slight letterboxing. All widescreen content on ABC Family's SD feed is presented in

this ratio.

1.60:1 (8:5, 16:10): Widescreen computer monitor ratio (for instance 1920×1200

resolution).

1.66:1 (5:3, 15:9): 35 mm Originally a flat ratio invented by Paramount Pictures, now

a standard among several European countries; native Super 16 mm frame ratio.

Sometimes this ratio is rounded up to 1.67:1. From the late 1980s to the early

2000s, Walt Disney Feature Animation's CAPS program animated their features in

the 1.66:1 ratio (a compromise between the 1.85:1 theatrical ratio and the 1.33:1

ratio used for home video), this format is also used on the Nintendo 3DS's top

screen as well.

1.75:1 (7:4): Early 35 mm widescreen ratio, primarily used by MGM and Warner

Bros. between 1953 and 1955, and since abandoned, though Disney has cropped

some of its post-50's Full Screen films to this ratio for DVD, including The Jungle

Book.

1.77:1 (16:9 = 42:32): Video widescreen standard, used in high-definition television,

one of three ratios specified for MPEG-2 video compression. Also used increasingly

in personal video cameras. Sometimes this ratio is rounded up to 1.78:1.

1.85:1: 35 mm US and UK widescreen standard for theatrical film. Introduced

by Universal Pictures in May, 1953. Projects approximately 3 perforations ("perfs")

of image space per 4 perf frame; films can be shot in 3-perf to save cost of film

stock.

2.00:1: Original SuperScope ratio, also used in Univisium. Used as a flat ratio for

some American studios in the 1950s, abandoned in the 1960s, but recently

popularized by the Red One camera system. In 2001 Studio Ghibli used this

framing for its animated filmSpirited Away.

2.10:1 (21:10): Planned futuristic aspect ratio for television and theatrical films.

2.20:1 (11:5, 22:10): 70 mm standard. Originally developed for Todd-AO in the

1950s. Specified in MPEG-2 as 2.21:1, but hardly used.

2.35:1: 35 mm anamorphic prior to 1970, used by CinemaScope ("'Scope") and

early Panavision. The anamorphic standard has subtly changed so that modern

anamorphic productions are actually 2.39,[1] but often referred to as 2.35 anyway,

due to old convention. (Note that anamorphic refers to the compression of the

image on film to maximize an area slightly taller than standard 4-

perf Academyaperture, but presents the widest of aspect ratios.) All

Indian Bollywood films released after 1972 are shot in this standard for theatrical

exhibition.

2.37:1 (64:27 = 43:33): As of 2010, TVs have been introduced with this aspect ratio

and are marketed as "21:9 cinema displays". This aspect ratio is not recognized by

storage and transmission standards.

2.39:1 (~12:5): 35 mm anamorphic from 1970 onwards. Aspect ratio of current

anamorphic (wide-screen) theatrical viewings. Often commercially branded

as Panavision format or 'Scope. Specified as 2.40:1 for Blu-ray Disc film releases

(1920×800 resolution).

2.55:1 (~23:9): Original aspect ratio of CinemaScope before optical sound was

added to the film in 1954. This was also the aspect ratio of CinemaScope 55.

2.59:1 (~13:5): Cinerama at full height (three specially captured 35 mm images

projected side-by-side into one composite widescreen image).

2.66:1 (8:3, 24:9): Full frame output from Super 16 mm negative when an

anamorphic lens system has been used. Effectively, an image that is of the ratio

24:9 is squashed onto the native 15:9 aspect ratio of a Super 16 mm negative.

2.76:1 (~11:4): Ultra Panavision 70 (65 mm with 1.25× anamorphic squeeze). Used

only on a handful of films between 1962 and 1966, such as the Battle of the Bulge

(1965).

2.93:1: MGM Camera 65, an early version of Ultra Panavision used up until 1962

which used a 1.33× anamorphic squeeze instead to produce a wider aspect ratio.

Used only on a few early Ultra Panavision films, most notably Ben-Hur (1959) and

also for some sequences of How The West was Won with a slight crop to 2.89:1

when converted to three strip Cinerama.

4.00:1: Rare use of Polyvision, three 35 mm 1.33:1 images projected side by side.

First used in 1927 on Abel Gance's Napoléon.

12.00:1: Circle-Vision 360° developed by the Walt Disney Company in 1955 for use

in Disneyland. Uses nine 4:3 35mm projectors to show an image that completely

surrounds the viewer. Used in subsequent Disney theme parks and other past

applications.

[edit]Aspect ratio releases

[edit]Original aspect ratio (OAR)

Original Aspect Ratio (OAR) is a home cinema term for the aspect ratio or dimensions

in which a film or visual production was produced – as envisioned by the people

involved in the creation of the work. As an example, the film Gladiator was released to

theaters in the 2.39:1 aspect ratio. It was filmed in Super 35 and, in addition to being

presented in cinemas and television in the Original Aspect Ratio of 2.39:1, it was also

broadcast without the matte altering the aspect ratio to the television standard of 1.33:1.

Because of the varied ways in which films are shot, IAR (Intended Aspect Ratio) is a

more appropriate term, but is rarely used.

[edit]Modified aspect ratio (MAR)

Modified Aspect Ratio is a home cinema term for the aspect ratio or dimensions in

which a film was modified to fit a specific type of screen, as opposed to original aspect

ratio. Modified aspect ratios are usually either 1.33:1 (historically), or (with the advent of

widescreen television sets) 1.77:1 aspect ratio. 1.33:1 is the modified aspect ratio used

historically in VHS format. A modified aspect ratio transfer is achieved by means of pan

and scan or open matte, the latter meaning removing the cinematic matte from a 1.85:1

film to open up the full 1.33:1 frame. Another name for it is "prescaled" aspect ratio".

[edit]Problems in film and television

A windowboxed image

Multiple aspect ratios create additional burdens on filmmakers and consumers, and

confusion among TV broadcasters. It is common for a widescreen film to be presented

in an altered format (cropped, letterboxed or expanded beyond the Original Aspect

Ratio). It is also not uncommon for windowboxing to occur (when letterbox and pillarbox

happen simultaneously). For instance, a 16:9 broadcast could embed a 4:3 commercial

within the 16:9 image area. A viewer watching on a standard 4:3 (non-widescreen)

television would see a 4:3 image of the commercial with 2 sets of black stripes, vertical

and horizontal (windowboxing or the postage stamp effect). A similar scenario may also

occur for a widescreen set owner when viewing 16:9 material embedded in a 4:3 frame,

and then watching that in 16:9. Active Format Description is a mechanism used in digital

broadcasting to avoid this problem. It is also common that a 4:3 image is stretched

horizontally to fit a 16:9 screen to avoidpillar boxing but distorts the image so subjects

appear short and fat.

Both PAL and NTSC have provision for some data pulses contained within the video

signal used to signal the aspect ratio (See ITU-R BT.1119-1 – Widescreen signaling for

broadcasting). These pulses are detected by television sets that have widescreen

displays and cause the television to automatically switch to 16:9 display mode. When

4:3 material is included (such as the aforementioned commercial), the television

switches to a 4:3 display mode to correctly display the material. Where a video signal is

transmitted via a European SCART connection, one of the status lines is used to signal

16:9 material as well.

[edit]Still photography

Common aspect ratios in still photography include:

1:1

4:3 (1.33:1)

3:2 (1.5:1)

5:3 (1.66:1)

16:9 (1.77:1)

3:1

Many digital still cameras offer user options for selecting multiple image aspect ratios.

Some achieve this through the use of multi-aspect sensors (notably Panasonic), while

others simply crop their native image format to have the output match the desired image

aspect ratio.

[edit]1:1

is the classic square image, and is available as a choice in some digital still cameras,

and harkens back to the days of film cameras when the square image was somewhat

popular with photographers using medium format cameras shooting 120 film rolled onto

spools. The 6 × 6 cm image size was the classic 1:1 format in the recent past. 120 film

can still be found and used today.

[edit]4:3

is used by most digital point-and-shoot cameras, Four Thirds system, Micro Four Thirds

system cameras and medium format 645 cameras. The 4:3 digital format popularity was

developed to match the then prevailing digital displays of the time, 4:3 computer

monitors.

The next several formats have their roots in classic film photography image sizes, both

the classic 35 mm film camera, and the multiple format Advanced Photo System (APS)

film camera. The APS camera was capable of selecting any of three image formats,

APS-H ("High Definition" mode), APS-C ("Classic" mode) and APS-P ("Panoramic"

mode).

[edit]3:2

is used by classic 35 mm film cameras using a 24 mm × 36 mm image size, and their

digital derivatives represented by DSLRs. Typical DSLRs come in two flavors, the so-

called professional "full frame" (24 mm × 36 mm) sensors and variations of smaller, so

called "APS-C" sensors. The term "APS" is derived from another film format known as

the APS and the "-C" refers to "Classic" mode, which exposed images over a smaller

area (25.1 mm × 16.7 mm) but retaining the same "classic" 3:2 proportions as full frame

35 mm film cameras.

When discussing DSLR's and their non-SLR derivatives, the term APS-C has become

an almost generic term. The two major camera manufacturers Canon and Nikon each

developed and established sensor standards for their own versions of APS-C sized and

proportioned sensors. Canon actually developed two standards, APS-C and a slightly

larger area APS-H (not to be confused with the APS-H film format), while Nikon

developed its own APS-C standard, which it calls DX. Regardless of the different flavors

of sensors, and their varying sizes, they are close enough to the original APS-C image

size, and maintain the classic 3:2 image proportions that these sensors are generally

known as an "APS-C" sized sensor.

The reason for DSLR image sensors being the flatter 3:2 versus the taller point-and-

shoot 4:3 is that DSLRs were designed to match the legacy 35 mm SLR film, whereas

the majority of digital cameras were designed to match the predominant computer

displays of the time, with VGA, SVGA, XGA and UXGA all being 4:3. Widescreen

computer monitors did not become popular until the advent of HDTV which uses a 16:9

image aspect ratio.

[edit]16:9

16:9 is another format that has its roots in the APS film camera. Known as APS-H

(30.2 mm × 16.7 mm), with the "-H" denoting "High Definition", the 16:9 format is also

the standard image aspect ratio for HDTV. 16:9 is gaining popularity as a format in all

classes of consumer still cameras which also shoot High Definition (HD) video. When

still cameras have an HD video capability, some can also record stills in the 16:9 format,

ideal for display on HD televisions and widescreen computer displays.

[edit]3:1

is another format that can find its roots in the APS film camera. Known as APS-P (30.2 ×

9.5 mm), with the -P" denoting "Panorama", the 3:1 format was used

for panorama photography. The APS-P panorama standard is the least adhered to of

any APS standard, and panoramic implementation varies with by manufacturer on

different cameras, with the only commonality being that the image is much longer than it

is tall, in the classic "panorama" style.

Common print sizes in the U.S. (in inches) include 4×6 (1.5), 5×7 (1.4), 4×5 and 8×10

(1.25), and 11×14 (1.27); large format cameras typically use one of these aspect

ratios. Medium-formatcameras typically have format designated by nominal sizes in

centimeters (6×6, 6×7, 6×9, 6×4.5), but these numbers should not be interpreted as

exact in computing aspect ratios. Print sizes are usually defined by their portrait

dimensions (tall) while equipment aspect ratios are defined by their landscape

dimensions (wide, flipped sideways). A good example of this a 4×6 print (6 inch wide by

4 inch tall landscape) perfectly matches the 3:2 aspect ratio of a DSLR/35 mm, since

6/2=3 and 4/2=2.

For analog projection of photographic slides, projector and screen use a 1:1 aspect

ratio, supporting horizontal and vertical orientation equally well. In contrast, digital

projection technology typically supports vertically oriented images only at a fraction of

the resolution of landscape-oriented images. For example, projecting a digital still image

having a 3:2 aspect ratio on a 16:9 projector employs 84.3% of available resolution in

horizontal orientation, but only 37.5% in vertical orientation.