week 7 Flashcards
Three properties of light
Wavelength
frequency
intensity
Light has both blank and blank properties
Electric and magnetic
light travels in ____
waves
What is the difference between light waves and audio or ocean waves
light waves move in different direction
What are four types of EMR wavelength that are safe
Radio, microwaves, IR, visible
What are three dangerous EMR waves
UV, x-ray, gamma
when light waves encounter objects what four things can they do
Reflect, absorb, pass through, refract
When light waves in counter objects what happens
Multiple colours of light encounter objects and appear as white light
White light is made up of a whole bunch of different___
Wavelengths of light
What is chromatic aberration
When all the various wavelengths aren’t bent exactly the same
What do we call it when various wavelengths are not bent exactly the same
Chromatic aberration
What is the wavelength of light in nanometers
From 400 to 700 nanometers
The frequency of visible light is called what
Colour
What is the range of visible light/color in hertz (Hz)
430 trillion hertz to 750 trillion hertz
What colour can be seen at 430, trillion Hz
red
What colour can be seen at 750 trillion Hz
violet
what are footcandles
1 foot candle is the amount of light on a 1 inch square surface
Created from a source of light that is 1 foot away from the source
How many foot candles is full unobstructed sunlight
10,000 foot candles
How many foot candles are cloudy days
Around 100 foot candles
What is Lux
Lux is the amount of light being generated at a defined distance
What is the formula for converting lux to foot candles
10.76 Lux = 1 foot candle
What are two ways to measure light
Lux and foot candles
What are two tools used to measure light
Reflective meter
and incident meter
What is a reflective metre
Measures how much light as being reflected back into the metre
What is an incident metre
How much light is hitting the surface of the metre
What is the acronym for qualifying light
D
I
S
C
What does disc stand for
Direction, intensity, softness, colour
How do I tell which direction the light is coming from
Observed through the shadow
How do you define intensity of light
Relationship between source and ambient light level
It changes based on the proximity of the light to the source
If one light exhibit more intensity than others this is understood through an increase in perceived contrast
How is softness defined
By the shadow the light creates
By the size of the light source relative to the subject being illuminated
What is a hard shadow versus a soft shadow
A hard shadow is a well defined
a soft shadow lesser defined edges
How is the colour of a light measured
Degrees kelvin
What are 4 degrees kelvin colours to know
Tungsten halogen
Household fluorescent
Noon sunlight
LCD monitor
From yellow to blue which order do the 4 kelvin colours go in
yellowest: tungsten
blue-whiteish: household fluorescent
pale blue: noon sunlight
bluest: LCD monitor
What are contrast ratio’s
Relationship between the key light and fill light
How are contrast ratio is measured
The doubling of light
What is fill light
How many times brighter
Three elements of power
Amperage
Voltage
Wattage
What is amperage/amps
How much power is flowing
What is voltage/volts
The pressure/intensity at which the power is flowing
What is wattage/watts
Energy created or energy required
How many amps is the average circuit
15 amps
One amp Powers how many watts
1 amp powers 100 Watts
What are four elements of tungsten lights
They have black body radiators
They draw high energy
They get hot around 3200 Kelvin
They are dimmable
What are five properties of fluorescent lights
gas mixture ignited and controlled by ballast
Different colour temperatures
They draw low energy
The output softer light
They are non-dimmable
Five properties of HMI lights
- hydrargydum
- Gas mixture ignited and controlled by a ballast
- Daylight colour temperature
- Draws low energy
- emits UV light
What are five properties of LED lights
Light emitting diode’s
Range of temperature and colours
Very low energy
Many small point sources
Often dimmable
Which two types of light have a gas mixture ignited and controlled by ballast
HMI and fluorescent
Which lights get very hot
Tungsten
Which lights are non-dimmable
Fluorescent
Which three lights dry low energy
Fluorescent HMI and LED
Which type of light draws the lowest energy
LED lights
What are two light locations of Frenzel
Flood and spot
What is the difference between Flood in Spot in a Fresnel light
Flood is when the lightbulb is close to the lens
Spot is when the lightbulb is far away from the lens
What is the wattage range of a frensel light
100 W to 50,000 W
What are barn doors
Used to control the area of illumination
What will narrowing the barn doors do
Result in a narrower shaft of light
What are three elements of a broad light
Very soft
Hard to control
Barn doors have no effect
what is an ellipsoidal also known as
A pattern projector
What are cyc or strip lights
Designed to cast light down or up cyclorama walls
What will black bouncers or reflectors do
Add depth and shadows
Block unwanted light and reflections
What will white bouncers and reflectors do
Soften and reflect light
Will not change the colour temperature
What will silver bouncers and reflectors do
Reflect light
Add contrast or sharp highlights
What will gold bouncers and reflectors do
Add a hint of warmth
Subtle contrast by reflecting light
What are three lighting modifiers
Silk
flag
net
What will silk light modifiers do
Defuse and soften light
What will flag modifiers do
Block/cut light
What will NET modifiers do
Reduce intensity
What does DMX stand for
Digital Multiplex
What do you DMX digital multiplex lights do
Controlled via a lighting board or an app
Allows you to adjust lighting from the ground
