Aspect ratios: Anamorphic Widescreen elements that make DV more filmic

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Aspect ratios Anamorphic Widescreen elements
that make DV more filmic

• Lighting/Gels
• Sound quality and design
• Camera movement Jib/Tracking
• Aspect ratio (16.9)
• Progressive scan/De/Interlacing/frame mode.
• Lens type (Wide angle, Prime, Telephoto/Zoom/Macro
  
• and Normal)
• Filters

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Aspect ratio The relationship between the width
of a film image and its height is known as its
aspect ratio.

• 1890s -1950s, almost all films standard aspect
  ratio of 1.331. (Technically 1.371, but
  1.331).
• "1.33" refers to the width, in units, in
  comparison to the height of the frame unit, which
  is always "1".
• The colon separates the two units and should be
  expressed as "to".
• this reads as "one-point-three-three to
  one".
• For every one unit high the image is, it
  correspondingly is 1.33 units wide (4x3,
  meaning 4 units of width for every 3 of height).
• Known as Academy Standard (recognized by
• Academy of Motion Picture Arts and Sciences
• in the 1930s)

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Dracula (1931) and Gone with the Wind (1939)
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1950s - National Television Standards Committee
(NTSC), selected Academy Standard as the official
aspect ratio.

• Transferring to TV in the Academy Standard aspect
  ratio was not a problem - similar ratio to TV
  set.
• "4x3" -industry reference to current TVs.
• 1950s TV began to attract more viewer interest
  than Hollywood.
• So the film industry began to change the look of
  film.
• After 50s 20th Century Fox introduced the world
  to the CinemaScope used 1953-1967.
• Eventually Panavision became the most used
  widescreen process.
• Today, widescreen dominates filmmaking in a
  variety of aspect ratios.
• Two "standardized" ratios that are the most
  common
• Academy Flat (1.851) and Anamorphic Scope
  (2.351).
• less used ratios include 1.661 and 2.201 (70mm).

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• Academy Flat
• Film is 1.85 times as wide as it is tall
  (referred to as "Flat").

• Anamorphic Scope
• Wider - 2.35 times as wide as it is tall
  (usually called "Scope").
• Scope films include Star Wars, Apocalypse Now and
  Blade Runner.

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Wider aspect ratio enhances dramatic impact
But Both Scope (2.351) and Flat (1.851) aspect
ratios have problems with full frame
presentation.
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Problems - Transferring films to TV

• Wider aspect ratios are too wide to fill TV
  screen vertically if seeing the whole image
  horizontally.
• Pan scan process
• letterbox transfers
• Pan scan Can be referred to as "full frame
• Film is "modified" to fit TV screen.
• Most film enthusiasts prefer letterbox format.
• ENTIRE film image with black bars filling the
  unused screen area at top and bottom of the frame

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Pan scan transfer.

• The video camera "pans and scans" back and forth
  across the film image to keep the most important
  action centered on your TV screen.
• The problem - as much as 50 of the film's
  original image can be lost in the process.
• Composition of objects and movement within the
  frame is destroyed.

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Widescreen vs. Full Frame (pan and scan) -
2.351 Ratio Films
Blade Runner
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Letterbox transfer

• To view a movie in aspect ratio originally
  intended by director.
• view widescreen movies in the letterbox format
• ENTIRE film image is presented, and black bars
  fill the unused screen area at the top and bottom
  of the frame.
• Problem -letterbox viewing a loss of vertical
• picture resolution.
• The black bars take up part of the screen on your
  TV, leaving less picture area for the actual film
  image.
• Anamorphic widescreen can resolve this problem.

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(1.851Flat) 4x3 TV screen
(2.351Scope)
While some vertical picture resolution is
sacrificed, the director's original widescreen
composition is preserved
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Aspect Ratios

• o 1.331 Academy (4x3)
• o 1.661 European Super 16mm
• o 1.781 U.S. Digital TV HDTV
• Anamorphic widescreen - (16x9)
• o 1.851 U.S. Wide Screen
• o 2.351 Scope (Anamorphic scope)
• NB refer to class test articles in DISM folder
  (www.filmtechnology. Info) for more information.

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Anamorphic Widescreen

• Aspect ratio - 1.781 (also known as 16x9) will
  be the future of TV widescreen.
• If a widescreen movie is recorded in the
  anamorphic format, a Digital Projector or TV can
  "unsqueeze" the image.
• It fills the full width of the TV screen, while
  retaining more vertical resolution.
• Still not full high definition (HDTV) but more
  than on Standard TV.
• How Does Anamorphic Work?
• During an anamorphic transfer during projection
  or the telecine stage. (e.g. HD)
• Authoring software allows the DVD player and DTV
  to recognize the anamorphic signal.
• Displaying anamorphic widescreen and standard
  letterbox (non-anamorphic) aspect ratios.

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Avid Anamorphic (16x9) Anamorphic Scope
(2.351)

• 16x9 is becoming the standard for all (HDTV).
• From earliest proposed HDTV format.
• In this 1920 pixels (wide) x 1080 pixels (high)
• Divide 1920 by 1080 ratio 1.77777781
• but to make it simpler divide 16 by 9
  1.7777778.
• To display larger film image
• 1. During either shooting or the telecine
  process, use a 169 lens to squeeze the film
  images anamorphically to the 43 aspect ratio.
• 2. After capturing the footage, select Clip gt
  169 Monitors to return the squeezed image to its
  normal aspect ratio. The picture is larger.
• Any masked letterbox area at the top and bottom
  of the footage is smaller or might not be visible
  once it is set to 169.

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Avid Masks
43
1.69
1.66
185
Anamorphic
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Avid Masks
43
1.69
1.66
185
Anamorphic Scope 2.351
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Film masks, effects and techniques can also be
found under ( Illusion FX and Film)
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Interlaced Scanning/ Progressive Scanning

• Usual method of displaying TV images
• Scanning method reduces transmitted TV picture's
  bandwidth and works in accordance with
  electricity supply frequency (50Hz in the UK and
  Europe and 60Hz in the US).
• Result in interlaced scanning
• Each TV frame in two parts, called 'fields'
• Each field contains half of the scan lines of a
  frame. 1st field odd lines, 2nd field even
  lines.
• The even lines are interlaced between the odd
  ones to 'fill in the gaps'.
• In the 50Hz PAL system, each TV frame lasts
  1/25sec, with the electron gun scanning each
  field in 1/50sec.
• Interlaced scanning produces good pictures, but
  visible line and flickering caused by switching
  between two fields.
• With progressive scanning
• frames are not split into two fields of odd and
  even lines.
• Instead all image scan lines are drawn in one go
  from top to bottom.
• Sometimes referred to as 'sequential scanning' or
  'non-interlaced'.
• The fact that frames are shown as a whole makes
  it similar film

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field

• One-half of the scan lines in an interlaced video
  frame.
• In most systems, the odd-numbered lines form one
  field, and the even-numbered lines form the
  second.
• NTSC video contains approximately 60 fields (30
  frames) per second, and PAL video contains 50
  fields (25 frames) per second.

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Film and video transfer The 2-3 Pull Down

• Film intended for projection in cinemas - shot at
  24 fps and video travels at a different rate.
• PAL- 25 fps
• NTSC 30fps needs to be transferred to 24 fps.
• Each frame of video consists of 2 fields - each
  field contains half the frames total lines, which
  are scanned horizontally.
• This means that during transfer, the telecine
  machine places 4 frames onto 5 frames of video.

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Gamma

• A measurement of the midpoint in the luminance
  range of an image.
• Used in color adjustments to control the
  proportions of brighter and darker areas in an
  image.
• Also called the gray point.

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Camera Lenses - Wide-angle, Normal, Telephoto
and Zoom. (terms refer to the focal length of the
lens)

• Focal length - defined as distance from the
  center of the lens to the image it
• forms when the lens is set at infinity.
• In practice, focal length affects the field of
  view, magnification, and depth of field of a
  lens.
• In 35-mm photography Lenses with Focal lengths
  from
• 20 to 35 mm are considered wide-angle lenses.
  (Providing - greater depth of field and a larger
  field (or angle) of view with relatively low
  magnification.
• 45 to 55 mm are referred to as normal lenses -
  because they produce an image that approximates
  the field of view of the human eye.
• 85 mm or more are considered telephoto - longer
  focal lengths, called telephoto lenses, constrict
  the field of view and decrease the depth of field
  while greatly magnifying the image.
• Zoom lens- designed to have a variable focal
  length, which can be adjusted continuously
  between two fixed limits.
• Anamorphic - Compresses image horizontally during
  filming and expands it again during projection to
  give a oblong, wide screen picture.

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Camera Lenses
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Filters
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Class Test

• NB refer to class test articles in DISM folder
  (www.filmtechnology.info) for more information.
• Check Avid and Cool Edit Tutorials and consider
  lectures so far.
• Next week Tim will cover PAL and NTSC
  broadcasting standards and Interlacing and
  progressive scan in more detail.