rtvf lecture 3 and 4

  1. three ways to identify mics
    "type" of sound converting system, mic's pickup pattern, and its physical form
  2. dynamic mics
    moving coil mic, simple and cheap, thin metal wire (coil) wrapped around a magnet which creates a magnetic field, rugged, self powered, EFP
  3. condensor mics
    capacitor mic, two parallel plates, one moving one stationary instead of magnet, since there is no magnetic field they need external power source (batter, AC or phantom power), cleaner sound, small
  4. polar pattern
    2-D drawing of a 3-D pickup pattern
  5. omnidirectional
    equally from all sides, pick up sounds most realistically, most studio mics
  6. unidirectional
    mostly from front, cardiod, susceptible to breath popping (plosives)-popfilter/windscreen solve it. exhibit proximity effect where bass is really loud when close-up, field
  7. more directional mics
    super cardioid, hyper cardioid, ultra cardioid, pars on the edges of these mics cancel sounds coming from the sides. must not be covered by hands.
  8. shotgun mics
    very directional, only picks up sound beyond a certain point (10-30') doesnt pick up right by mic
  9. hand-held/stand/desk
    dynamics, at Hofstra: Electro Voice (EV) 50s=omni. EV RE10/15/16s=unidrectional, ENG
  10. lavalieres
    condensers, Samson PM6s=omnidirectional, phantom only. Audio Technica 803s=omni, batteries & phantom, used with JVC field packages. Sony ECM55s=omnidirectional, batters & phantom for studio use, electric condenser mic
  11. wireless systems
    radio frequency (rf) mics that transmit on a very low powered radio band wave, subject to interference, dropouts in transmission and batteries running out. diversity systems have two antennas attached to the receiver, whichever picks up the transmission better is the active antenna
  12. parabolic reflector mic systems
    sports, plastic cone with mic in outside center pointed inward toward back of cone, cone collects sound waves and points them into mic, shock mounts allow vibrations from operators to be isolated, pick up sound up to about 150 ft, big ears from 500' away
  13. interruptible foldback systems
    headset or small speaker that goes in talents ear allowing producers and directors to directly communicate
  14. signal to noise ratio
    the amount of good electronic info to the bad. electronic info that can interfere with and degrade the signal. the higher the better! measured in dB
  15. volume
    amplitude, measured in dB using a volume unit meter. can also be measured in percentage of modulation where 100% is full volume. 0dB=100% 2 scales: % of modulation and dB.
  16. frequency and frequency response
    sound waves come from a sound source that vibrates air molecules causing a chain reaction of molecules that carries the energy to your ears. 1 sound wave=1 cycle.
  17. how frequency is measured
    determined by the number of cycles that a vibration completes in a particular time period (1 second). measured in cycles per second or Hertz. every vibration has a measurable frequency. adults hear from 20 Hz-16MHz. kids hear from 20 Hz-20 KHz
  18. humans perceive variations in frequency as changes in
    pitch. the relative highness or lowness of sound. higher the frequency, higher the pitch. tuning fork A is 440 Hz (dial tone), oscillator generated tone on the audio board is usually 1,000 Hz
  19. frequency response
    the ability of equipment to reproduce the original frequencies of the signal it is processing. all audio equipment should list frequency response specifications. CD players range from 5-20 kHz, iPods from 20-20kHz
  20. frequency spectrum
    audible frequencies, divided into sections, octaves, interval between two frequencies that has a 2:1 ratio. human hearing can discern 10, voice produces 3-4 up to 7. 12, 34, 567, 8910
  21. camera see ____
    reflected light from the image as opposed to incident light directly from a source.
  22. color temperature
    standard for measuring color of light, relate to theoretical "plotting" of colors of light if we were able to heat something that high. over 3,200 K light is red, at 3,200 K light is white. over is blue
  23. color temperature of tungsten/quartz-halogen lamp
    3,200 K typical studio lamp
  24. color temperature of fluorescent light
    3,500- 6,500 K green
  25. direct midday sunlight color temperature
    5,600 K
  26. HMI light
    5,600 K = average daylight color temperature
  27. cameras do not like to shoot
    mixed color temperatures, goal is to create a consistent color temperatre
  28. four ways to manipulate color temperature in order
    change light source, lighting gels (neutral density) or change color temperature Rosco calls them filters some are boosters to increase color temperature, color temperature filters (found on filter wheel to alter light towards 3200K), white/color balance with white screen or shoot grey scale/chip chart and paint camera using R&B color gain pots found on CCU
  29. two basic reasons for television lighting
    basic illumination, artistic or creative reasons
  30. basic illumination
    let cameras see their subjects and create usable picture. base light-minimum amount of light needed or clear pictures that are free of noise, in field boost the gain switch to electronically boost brightness level (lowers the S/N ratio, grainy)
  31. contrast ratio
    how many gradations are between the darkest and lightest picture areas. human eye=1000:1, cable 25:1
  32. footcandles
    main measure of the amount of light present, amount of light given off by one lumen light source in one square foot area, using CCD cameras there should be about 110-160 footcandles on a subject. key lights produce 125. fluorescent lights are cooler, last longer, skin looks sickly if not color balanced
  33. artistic or creative reasons
    define shape and texture of the physical form, imitate light characteristics, establish and enhance mood
  34. practical aspects of studio light
    simple, 3 point light lighting, plot carefully, aim correctly, trim lights: high key-fill light be half of key light. low key- fill light be 3 quarters as bright as key light back light should be equal to key light. blue light stimulates darkness to maintain proper color temperature
  35. zebra patterns
    in viewfinder modulating cross hatched patterns, open iris until pattern emerges, IRE is unit of measure for measuring voltage, corresponding to % of full brightness that images should be displayed at
  36. use a waveform monitor to check
    for proper contrast blacks no lower than 7.5 IRE whites no higher than 100 IRE , white faces peak around 75 IRE, waveform should be flat line across monitor
  37. control the light by
    using barn doors, spots v floods, flags, diffusion to decide where light will go
Card Set
rtvf lecture 3 and 4