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Characteristics
of Light
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Properly lighting an event
for video coverage is more than a matter of making it
"bright enough." Be sure your lighting contractor
understands the nature of the event and lights it to
address the specific needs of the event and not fit
what can be done with the contractor's "standard
lighting package."
The lighting production company will appreciate that
you understand their work is more complex than flipping
a switch, and you will get a better end result as well! |
Intensity
(Brightness)
Quality (Hardness of softness)
Contrast (Relative difference
in brightness between the brightest and darkest areas)
Direction (Relative to the audience
or the camera)
Color Temperature |
INTENSITY
| Light source |
Foot candles |
| Bright sun |
5,000-10,000 |
| Hazy sun |
2,500-5,000 |
| Bright sun, cloudy |
1,000-25,000 |
| Dull cloudy |
200-1,000 |
| Very dull |
10-200 |
| Sunset |
0.1-10 |
| Full moon |
0.001-0.01 |
| Television Studio |
100-200 |
| Office |
20-30 |
| Living Room |
5-20 |
| Corridors |
5-10 |
| Good street lighting |
1-2 |
| Dim street lighting |
0.1-.01 |
| Candlelight (20 cm away) |
1.5 |
QUALITY
Light varies along a scale of hardness
to softness, depending on the source and the distance from
the source to the subject. Hard light is directional,
and focused -- a beam. Hard light causes distinct shadows.
By contrast, soft light is diffuse and shadowless.
CONTRAST
The relative difference between
the brightest and darkest areas of a scene. If a subject is
twice as bright as the background, the contrast ratio is 2:1.
Video cameras can accurately interpret intermediate lighting
levels if the contrast range is 30:1 or less. This is why
it is important to light the background of a scene.
DIRECTION
Appearance of a subject will vary
tremendously depending on the direction of hard light on the
subject. Frontal lighting will flatten a subject. The further
off center (either vertically or horizontally) the light source,
the more it will accentuate the texture of the subject. This
is especially important with people's faces -- lighting direction
can drastically change the appearance of wrinkles, for instance.
COLOR TEMPERATURE
| Typical color temperatures |
Kelvin |
| Candle |
1,930K |
| Household tungsten lamp (25-250
W) |
2,600-2,900K |
| Studio tungsten lamp (500-1,000
W) |
3,000K |
| Studio tungsten lamp (2,000
W) |
3,275K |
| Studio tungsten lamp (5 kW
or 10 kW) |
3,380K |
| Quartz (tungsten-halogen or
T-H) lamp |
3,200-3,400K |
| Photoflood |
3,400-3,500K |
| HMI (Hydrargyrum medium arc-length
iodide) |
5,600-6,000K |
| Fluorescent lamp |
3,000-6,500K |
| Sunrise and sunset |
2,000-3,000K |
| Morning, one hour after sunrise |
3,500K |
| Sunless daylight |
4,500-4,800K |
| Midday sun |
5,000-5,400K |
| Overcast sky |
6,800-7,500K |
| Hazy sky |
8,000-9,000K |
| Clear blue north sky |
10,000-20,000K |
Variations of +/- 150K are generally
acceptable when matching light sources.
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