T356 Week 5 - Spring 2013
- Wrap up lighting
- Audio / Lighting Quiz next week!
- Demonstration video pitches next week in lab!
- Talk about PSA Proposals, Demonstration Videos (due next week) and News stories (due the following week)
Readings: don't forget to do the cybercollege readings. Audio units:
37, 38, 39, 40 and 43.
Misc Announcements & Updates:
PSA Proposals - Please remember that these are due in lab this week. Here's a link to the Service Learning clients who would like PSAs produced for them. It's vital that you take on a project for an actual client and that you communicate with them to determine their needs- BEFORE you submit your proposal.
Graphics Lab / Demonstration Video materials - Next week we'll have a lighting / audio quiz in lecture and start covering graphics. We'll meet here for lecture as usual- but the labs will be in a computer lab (BLBH 107). In lab we'll cover Photoshop and you'll also pitch your Demonstration Videos. Please note that you'll have to submit a full pre-production packet for your Demonstration Video. This is worth 15 points and includes:
- Program Proposal (includes title, objective, target audience, show description, production overview)
- Treatment or Script (partial script format can be used which includes intro, talk points, segues and close)
- Storyboarded key shots (Just include a few of the key shots.)
- Floor plan & lighting plot
The week after next is our News/chromakey exercise.
Will cover in lab next week. Students will have to write a 30-second
news piece and prepare 2 graphics.
Wrapping Up Lighting------------------------
(Finish notes from last week.)
Studio lighting and set design tips:
Before designing and building sets think about what you want to see in the frame. Storyboard your key shots first. Then create a floor plan and lighting plot to match. If you are producing a talk show you might want consistent light and colors behind the MCUs of your guests. If you are producing a noir piece you might want room to see shadows.
Keep furniture (couches, tables, chairs, etc.) away from flats (at least 8 feet or so) or your lighting angles will be too high from having to shoot over the flats.
Keep key lights off of the set as much as possible. This way you can
control them separately from the talent. (You need proper light
placement & set design to ensure you can do this.)
Scoops can work well to illuminate walls. Make sure they are hitting only the wall and not hitting the floor space. They can also be used to add a little touch of fill.
Use fresnels to create overlapping pools of light - Think about the areas where your actors need to be (in doorways, sitting at dining tables on couches, etc.). For most of these talent marks/areas, you'll need more than one key light.
Use multple fresnels (NOT FLOODS) to make overlapping pools of light in these areas.
Realistic lighting: Try to have believable lighting. Visible lighting fixtures that are part of the set (a light next to a bed for example) can make a huge difference.
Aim to get around 65-70 IRE for Caucasian skin tones under daylight.
(Evening/night scenes or darker-colored skin will be less.)
Try to get sets and flats about 20 IRE below the talent.
Audio for film and video is more than just recording a good signal. Most soundtracks are multi-layered creations that go far beyond providing us with dialogue. We hear cues that tell us where they are- outside, inside, who’s sitting on the left or right, how big the room or environment is. How many people are milling about in the background and what they are doing? Maybe what the weather is like.
You could place two people at a table in a restaurant set and record pristine audio with a $2,000 microphone. It might sound great, but it’s not going to fly with a TV audience. It would sound weird. Viewers expect to hear clinking silverware, the murmur of other diners and music playing over the sound system. A classy restaurant on Friday night would sound much different than a diner on Saturday morning.
In a live studio environment, background tracks must be thought of
in advance. The production lab has a library of sound effects and a
minidisc recorder. Think of your location and get fitting sound effects
and music before you have to produce your project.
Loudness & Frequency
Loudness can be measured in decibels (dBs) and be represented visually with VU meters.
Metering & Level Setting: Analog vs. Digital
Analog (quickly becoming obsolete)
- The scale on a VU meter goes from –20 db to +3. We set the levels so most sounds are underneath 0 with the peaks going up into the red area.
- Common practice is to use a 1 kHz tone at 0 on the VU meter for reference purposes. For example we always record color bars at the beginning of tape. It should be accompanied with 1 kHz tone at 0 VU.
- Digital meters are different than analog. The scale starts at around -50 and goes up to 0. When we record the 1 kHz standard reference tone, we do it at –20 on the digital scale. (That's what we use in N America, European communities might use -14 or -18.)
- Just because a meter is digital doesn’t mean it’s for digital audio. Look at the numbering scale to determine if it’s for digital or analog audio.
Viewers expect sounds from far away to sound more distant and sounds
nearby to sound more present. We've been listening to stereo and surround
audio for years and are acustomed to taking cues of character positions
or locations through the soundtrack. Imagine a long shot in a busy restaurant
as our two stars enter and sit down at a table.
Over the long shot we'd expect to hear quite a bit of ambient sounds.
But then we cut into a closeer two shot, and the audio must sound more
intimate. In addition, there's stereo imaging. The audio from the person
on the left comes from the left side speaker. But then we cut in to the
character with a full screen close up. The sound then comes from the
This is why the boom mike is sometimes favored over lavalieres for recording
dialog. We can easily vary the distance so the audio perspective matches
the camera perspective.
Automatic gain control circuits try to get a consistent level. If it’s soft, it’ll boost the signal. If it’s loud it’ll turn it down. Don’t use it! It’ll bring the noise floor up and reduce your dynamic range.
Frequency is measured in Hertz or cycles per second
- Hertz = Hz or CPS cycles per second
- Kilohertz (kHz) = 1000 Hertz
- Human hearing generally ranges from 20 Hz to 20 kHz
- Concert A = 440 Hz
- Middle C is 261.63 Hz
- The human voice ranges from about 100 – 9,000 Hz
Impedance = resistance and is measured in ohms.
It's important that the output and input impedances match in production
- High impedance = High Z, low impedance = Low Z.
- Professional mics often have an impedance of around 150-200 ohms.
Other devices (like electric guitars) can have impedances up in the
thousands. You can use impedance matching transformers. (Plug an
electric guitar into a microphone input)
Microphones convert one form of energy to another: sound waves to electric energy.
Can be classified in many ways. Most useful are by:
characteristics (dynamic, condenser, ribbon, etc)
- Pickup patterns (omni, cardioid, etc.)
- Design (handheld, lavaliere, etc.)
- Dynamic - durable. Works opposite of a speaker. A coil moves within a magnetic field
- Condenser- need batteries or phantom power. A plate or diaphragm moves adjacent to a stationary, charged backplate. The capacitance between the two plates changes as the diaphragm moves modulating an electric current.
- Ribbon - delicate. A small ribbon moves inside a magnetic field
- Hyper-cardioid (Shotgun) Super Cardioid
- Bi-directional a.k.a. Figure eight
- Lavaliere (wireless are the norm) Great for TV production.
- Hand held
- Shotgun mic. (Typically used on a boom pole, also known as a fish
pole. Great for film and storytelling projects.)
- Contact microphone/transducer (pickups for instruments)
- Boundary effect or PZM
- Stands (floor & desk) obtrusive good for music; desk: obtrusive but have excellent audio quality (Leno, Letterman)
Proximity Effect - Sounds closer to the microphone
have an exaggerated low frequency response. (Part of the reason radio
announcers sound so "bassey" is because they are talking
right into the mic.)
Pop-filter - Stops the letters B, P and T from "popping". (Typically
a thin piece of fabric.)
Phase cancellation - Sound is a wave. When two mics
pickup the same sound they will either magnify it if they are in phase,
or reduce it if they are out of phase. Reducing the sound through multiple
mics is known as phase cancellation. To avoid it assign one microphone
s the primary pickup device for each source.
Phantom Power - A way to power condenser microphones over existing
XLR cables. Typically 48 volts. Can be generated by mixers and cameras.
Wireless receivers - Diversity have two antennas. Non-diversity have
Balanced vs. Unbalanced (XLR two conductor & ground).
Balanced cables have three wires and are far less prone to electrical
interference than unbalanced (2-wire) cables. Long cable runs of unbalanced
cables will also cause a loss in high frequencies.
Different line levels (+4 dBm & –10 dBm).
There are two different levels considered "line level". Professional
equipment uses a slightly hotter signal of +4 dBm. Consumer equipment
(such as CD players, VCRs, etc) uses -10 dBm. They are usually interchangeable,
but plugging a +4 output into a -10 dBm input will sound louder and
possibly clip or distort. Plugging a -10 dBm output from a piece of
consumer gear into the +4 input of a mixer will usually work fine,
except the signal might be slightly softer.
Running cables - Don't run cables adjacent to AC
power cords. Keep them separated as much as possible and cross them
at 90 degrees at intersections.
Audio control booth/production room
Audio Control Booth is used during actual production
Audio Production room is used for post. This is where audio sweetening takes place. Sweetening is the process of adding track & SFX, tweaking eq etc.
Try to visualize the signal flow through the mixer. The audio signal
enters at the top- where the preamp is. You can usually select line
or mic. Mic levels are brought up to line levels. Really hot line levels
are padded (resistance is added to reduce the gain) You don't want
audio to clip or distort (make diagram of limited window & square
Next you can have equalization & auxiliary sends (to effects, headphones, sub-mixes)
Lastly there is channel assign (depends on the number of outputs the console has) a pan pot, solo & mute buttons & a channel fader.
Output section contains master outputs for selected channels (eg 1-8 for an 8 channel board)
Boards are usually referred to as 16x2, 16x4. This is inputs verses the number of outputs.
In-line consoles don't use a separate output section. Each input has its own output.
Mix: combine signals
Phantom Power (48 volts) for condenser mics
Patchbay- connect the inputs to the outputs
Digital patchbay & routing (push a button instead of patching)
Calibration: make sure the record level matches the console output (0 vu) Basically make sure inputs match the outputs.
Outboard Gear -
- Reverb / SFX
- Compressors & Limiters
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