Transcript Introduction to Visual Communication

Introduction to Visual
Communication
Television
Television
• Like film – television is actually a series of
still images presented to the eye in rapid
succession
• Earliest experiments in 1890s
– Italian monk – Casselli
– Pictures by wire
Television
• Mechanical Television
• Paul Nipkow – scanning disk
– Nipkow disk
• John Loge Baird
– Scottish inventor working with BBC
– Launched the first system based on
mechanical scanning
Nipkow disk
Television
• Electronic television – cathode ray tube
• Vladimir Zworykin
– Iconoscope
• Philo T. Farnsworth
– Image Dissector
Electromagnetic yoke
Filament
Electron cloud
Electron stream
Electronic scanning
Beam splitter
White light
Color TV screens
Television standards
• National Television Standard Commission
(NTSC)
• Standard Definition (SDTV)
• 4:3 aspect ratio
• 525 lines of horizontal resolution
• 30 frames per second
• 60 fields per second
• 2 fields per frame
• Interlace scanning
Television standards
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High definition (HDTV)
16:9 aspect ratio
1080 lines of horizontal resolution
30 frames per second
Progressive scanning
Television production
• Originally all television was live – except
for films which were shown on TV
• Multiple cameras were connected to a
switcher
• Camera shots were selected in real time
and sent out over the air
Transmitter
Switcher
Videotape
• Ampex corporation invented the videotape
recorder
• Allowed television programs to be
recorded and “mistakes” could be
corrected
Quadruplex Videotape
Quadruplex
Helical scan
Helical scan
Live on Tape
Switcher
VTR
Isolated Camera
VTR
VTR
VTR
Film Style
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Single camera production
One camera – film or video
Each shot is recorded individually
Entire program is assembled in post
production through editing
• Most hour-long dramas and some sit-coms
Forcing perspective
• http://www.youtube.com/watch?v=TY_QV
S0hE8g&feature=related
Forcing perspective