T356 Week 4 - Spring 2013
- Quiz on Cameras
- Lighting today & next week. Quiz in two weeks.
- This week's lab assignment: 2 week, 4-part Exercise (Lighting/Set Design, Chyron, Audio & Talent)
Your PSA proposals are due next week. We'll spend 15 minutes in lab next week so you can share your projects.
If you haven't done so already, you need to contact a potential client organization and see if they want to have a PSA produced for them. There are a few potential clients through the Office of Service Learning.
Also, you should be working on your Demonstration Video proposal. We
will pitch ideas and share them in lab the week after next.
Here's a sample PSA proposal:
Client organization: Bloomington Animal Care and Control.
Contact: Laurie Ringquist, Executive Director
Objective: After watching the PSA, viewers will want to come down to the shelter and adopt a pet.
Target audience: Bloomington & Monroe County residents
Production Design: This 60-second PSA will feature an on-camera spokesman from the shelter and B-roll of pets who need homes. During the production Laurie Ringquist will appear on-camera talking about the pets in need of loving homes. We'll go to digital still pictures of the animals and close with a graphic providing the phone number and location.
Production notes: I will visit the animal shelter next week with my digital still camera and take pictures of pets in need of homes. I'll then transfer these images into the Chyron CG one week before my production.
Review / ? / Quiz
Cybercollege lighting units: 27, 28, 29, 30, 31, 32, 33 & 34.
Basic 3-point lighting (aka the lighting triangle) includes:
- Keylight: Primary light source. Illuminates the basic shape of the subject
- Backlight: helps separate the subject from the background, creates a figure-ground relationship.
- Fill light. Fills in dark areas. Slows/minimizes the falloff. (Fill light should NOT be used to remove unwanted shadows- or in other words to fix a problem. You are much better off removing the shadows through fixing/controlling the key light or using flags.)
Really a 4th element should be added:
- Background or Set lights. These set mood, locale etc of scene
Do not try to stick to the lighting triangle at all times for studio
lighting. It doesn't work for all applications- such as when a talk show
host needs to face the entire audience on both sides. The lighting triangle
is more geared towards non-moving subjects and single camera/portraiture setups.
Types of lighting instruments
Studio Lighting Instruments generally fall into two categories
Two subcategories include Fresnel & Ellipsoidal lights
Fresnel - usually ranked by the lamp's maximum bulb wattage.
The largest studio fresnels are usually about 5K. (Arri makes a 10k)
Studio 5 has Aces (1K) & Deuces (2K)
Ellipsoidal - much more directional and focusable than Fresnels. Can be anywhere from 500 - 2,000 watts. 750 watts is common. Examples include
- Pattern projectors (the Berkey Beams in Studio 5)
- Follow spots
Floodlights create softer light than spotlights. Some types include:
- Scoops: straightforward- they look like ice cream scoops
- Softlight/softbox: My favorite way to create soft key light for intimate interviews. (Sample brands include Chimera & Riffa lights). A spotlight is directed through a diffuser. Less shadows than a scoop
- Broad light: Brighter than a softlight. Shadows are more defined due to higher output and more focused light source.
- Strip/cyc lights: Used to light cycs. Several broad lights contained in a single unit. Good for overall even illumination of backdrops. Often found in theatres.
- Fluorescent floodlight bank. Cooler color temp (more blue/green) and run cooler (literally) than incandescents. Can be set up for any color temp Way cheaper than an HMI. Many (like the ones in Studio 5) can't be dimmed.
Warning - Using nothing but floodlights will make your scene or set look flat & dull.
We meausre color temperature with the Kelvin scale. The color temperature is determined by type of lamp. Lamps and their approximate color temps:
- Incandescent: bulbs are large. They become redder with age (3200k)
- Quartz or Tungsten Halogen: encased in a quartz bulb with halogen gas. Smaller & retains its color temp (3200k)
- HMI: Hydrargyrum Medium-arc Iodide. They have the same color temp as the sun. (5600k) so are often used for outdoor lighting. They use arc lamps with ballasts and are not cheap. The small ones are sometimes called sun guns.
- Fluorescent: Professional models usually have gel kits to match popular color temperatures. Inexpensive, consumer flourescent bulbs usually have green tints but can work well when mixed with other lights.
- LED: LED lighting has come into popularity as they are relatively inexpensive, draw little power relative to the output and can be gelled to match popular color temperatures.
Indoor vs. outdoors
- 3200 - Standard indoor color temp
- 5600 - Standard outdoor color temp - Remember that outdoor color temps vary throughout day. Can be anywhere from 4800-6500.
Lighting Control Equipment - Youshould become skilled at placing, securing and controlling the light. It can be broken down into:
- Mounting devices
- Light shaping (Focus & spill control)
- Intensity controls
Mounting devices: In Studio 5 we have a pipe grid & counterweight battens
- Pipe grid is stationary. 12 - 18 feet above studio floor. (Need a couple feet more for heat dissipation)
- Battens can be lowered & are used with counterweights & a pin rail systems
- C clamps & safety chains. You need a wrench to securely fasten (Not finger tight)
- Always use safety chain
- Floor stands- good for getting light lower or in odd places. C-stands are popular.
Light Shaping controls:
- Lens/lamp focus. Most spots can be focused from wide to spot. This affects the beam size.
- Barn doors. Help control light spill. (For instance you can stop the back light from shining into the camera lens & causing lens flare.)
- Flags. There are hundreds of different sizes and types of flags. A common size on large sets is 3' x 4'. These are usually mounted on a C-stand. Some flags are solid, others can contain diffusion material. Solid flags can be considered free roaming barndoors, and are used to stop unwanted light.
- Diffusers soften the light and reduce its intensity. Diffusers can come in the form of a cloth-like material (Tuff spun for example) or in the form of a gel.
- Scrims/screens - a mesh used to cover all or some of a light. Reduces output and softens light a tad.
- Gels - Colored gels and ND (neutral density) gels will reduce the output, without affecting the quality.
- Reflectors- Typically used in conjunction with other lights. Bouncing light off of a reflector can provide nice fill. (A sheet of foam core can work fine)
- Dimmers- reduce voltage. Come in two types: Manual (potentiometer) like on your wall dimmer; Electronic- small control voltage is manipulated, controlling a larger voltage. Often a lighting patchboard or patchbay is used in conjunction with a dimmer
Color temperature: make sure you WB under the actual lighting conditions
The camera actually adjusts the RG&B levels so that they match electronically
We measure intensity in lux or foot-candles. Light meters give us objective & accurate means of determining light intensity.
Lux (European) vs. foot-candle aka lumen (American).
- A lux is the amount of light that falls on the surface of a square meter using a candle as a light source burning one meter away
- A foot-candle is the amount of light that falls on the surface of a square foot using a candle as a light source burning one foot away
The inverse square law states that for every foot you move away from a light source, your intensity will drop off by 1/4
10.75 lux = 1 footcandle
Incident vs reflected light - Measured in two different ways!
- Incident light: the light falling on a subject or performance area
- Reflected light: the amount of light bouncing off or reflected from your subject
Baselight - The minimum operating light level the camera needs to register anything.
Cameo lighting - Background is black. Foreground (subject) is illuminated. (Like in Charlie Rose show)
Silhouette lighting - Background is illuminated. Subject is not lit. Create effect of dark figures against a background.
Broad verses Narrow or Downstage verses Upstage lighting
Quick interview example (Vimeo)
Be aware of placing your key light
Tips for good, general studio lighting:
Start with a vision of what you want to see in the frame. Illustrations,
storyboards or mockups are key. Once you know what you want to see,
build a set that provides a way to get the images and look you need.
Keep subjects/talent away from flats and backdrops. This lets you light
your talent seprately from the set.
First set the Key lights - Use separate, multple keys for each subject
or area. Keep angle of light under 45 degrees. (In other words don't
put the light anywhere over their heads.) Diffusion will soften light,
causing fewer shadows.
Add the backlights - A steeper angle (35 degrees) is OK, but avoid placing
them directly over the talent's head. The right colored gel can be a
nice touch and bring out the color in hair or clothing.
Light the set - Unless you're trying for the white background look, keep the light level of the set below that of the talent's. In other words keep the talent more illuminated than the background.
Fill light - After you've placed the key, back and set lights, add whatever fill is necessary (chances are you won't need much).
Lab (weeks 4 & 5)
Activity: Lghting & CG exercise)
Goal: Become proficient building simple sets & setting lights
Receive CG tutorial & practice winding cables
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