Television Productions And Lighting Techniques:

 In lighting there are two goals:
i. Get enough light
ii. Use the light you have to shape and define objects in the scene.  Lighting is often tried out "on paper" by using a lighting diagram before it's actually set. Many potential problems can be spotted in the process of constructing a lighting diagram. The lighting diagram will make it easier to see where those shadows might fall. One man, One camera The simplest type of lighting involves one camera shooting one subject. The subject is placed in the setting far enough away from any walls or backdrops to avoid casting shadows on the background near the subject. The camera is set up placing the subject in front of the backdrop.
1. Key Light:
It is first light to set up. It's positioned thirty to forty-five degrees to the side of the camera and should strike the subject at an angle of about forty-five degrees from vertical. This lighting angle is best for people with normal features. People with short noses or weak chins should be lit from a steeper angle to increase the length of the shadows cast under the nose or chin. Those with long noses should be lit with fewer angles to produce shorter shadows. Moving the light closer to the camera will reduce the amount of modeling in the face and make the subject appear heavier than he is. Conversely, moving the light farther from the camera will throw more of the face in shadow, making it appear narrower. The key light is focused
On the subject by putting the bulb in the "full spot" position and centering the beam on the subject. The light is then flooded out until a reasonable overall level is reached. "Reasonable" means you can generate sixty to seventy IRE units of video on faces with minimal video noise in the picture and enough depth of field for your purposes.

Back Light:
The back light is placed directly behind the subject, in line with the camera.
It, too, is set at a forty-five degree angle from vertical. The backlight is spotted down and aimed at the subject's neck. It is then flooded until it has about the same intensity as the key light. The back light should be adjusted to produce a crisp but subtle border around the subject. People with blonde (or missing) hair require less intensity. People with very dark hair require more. When the back light is still too bright in the full flood position, a scrim can be fitted in front of the housing to soften and reduce the light.

Fill Light:
Fill light is added on the side of the camera opposite the key light. Fill light should be about half the intensity of the key and back lights. It should also be softer, producing no harsh shadows. Often a broad, scoop, or soft light is used instead of a spotlight to provide fill. Fill lights are also frequently scrimmed to soften them and reduce their intensity.
Background:
Finally, background light is added to bring the background up to a level in the middle of the overall gray scale of the subject. Background lighting should be even and unobtrusive. The background shouldn't be made the center of attention with harsh or uneven lighting.

Television Production And Lighting Instruments:

There are four basic kinds of lights used in television.
 These May be
i. spot lights(with narrow beam it casts well-defined shadow)
ii. broad lights( wider beam and casts a softer shadow)
iii. flood lights (broad illuminated circular pattern with a diffuse shadow)
iv. soft lights (almost it doesn’t cast shadow)

The intensity and beam spread of spots and some other lights may be adjusted by moving the lamp forward or back in the lamp housing. When the beam is narrow and intense the lamp is "spotted down." When the beam is wide and more diffuse the lamp is "flooded out.” All lamps have not this adjustment.
Barn Doors:
Most lamps are fitted in a globe having "barn doors," which are black metal flaps fastened. These flaps are used to keep light from falling where it's not wanted. Mostly these are used on backlights, which can cause objectionable lens flare if their light falls the camera lens directly.
Scrims Disks:
Scrims are special disks of screen wire that are used to soften lights and it reduce light intensity slightly too. Different full or half scrims can be used to produce variables soften effects in the scene easily. Scrims can also be used in lamps as a protective grid against bulb explodes.
Bulbs:
Tungsten-Halogen bulbs are used for television lamps commonly. These bulbs don’t lose their brightness and correct color temperature throughout their lives.
Fitting Stands:
These are used to fastened fitting of the lighting used in the production.Barn doors are most of time are the parts attach on these stands.

Power Consumption
Television lights use much power during their usage. They range from 25 watts for DC camera lights up to as high as 5000 watts. Lights used for electronic news gathering (ENG) or electronic field production (EFP) normally ranges from 500 to 1000 watts each.

Television Production and Lighting

Television is a means of changing patterns of light into electrical signals for
storage or transmission and then recreating those patterns on a screen. In
order to do this well, the television camera must be presented with properly
lighten scenes. There are three important things in reference to lighten the best.
i. Level
ii. Contrast range
iii. Color temperature.

i. Level
Lighting levels can be adjusted by the adjustment of the incidental light that is entering the scene, that light is touching the subjects in the scenes.
The incidental light is measured in foot-candle, that is the amount of light produced by a candle at a distance of one foot.
For high-quality pictures you need something between fifty and two hundred-foot candles. Most cameras can be operated in light ranging from the minimum up to 10,00 foot-candles. The lighting range of the cameras is almost written on the shell of the camera, e.g .19 candles or .39 candles etc. When you see that lighting range in the scene is out of the ranges of the camera you should try to adjust it. Basically this all is because of the incidental lights, so adjust it. If there is too little light, you should add additional lightings. And if there is too much incidental light coming in the scene, then you are to use special neutral density filters on the camera.

   ii.  Contrast
Contrast refers to the difference in brightness from the darkest parts of a
Scene to the brightest. The amplitude of the video signal determines useful contrast for television.
Common digital video signals are 24-bit color, with eight bits each for red,
green, and blue. This allows for 256 individual shades from dark to
light for each color. So 24-bit color allows all colors to be shown.
If contrast is low many receivers will produce a flat picture which do not clear the scene’s details. If contrast is much high details in the brightest and darkest parts of the picture will be lost. then Picture will look too heavy and colory that we be not ready to watch the detail of the scenes.So contrast is actually light reflected from the subject.

iii. Color Temperature
The third thing is color temperature. Every source of light has a
Characteristic color. This color is related to its "temperature." Lower color
Temperatures tend to be red or orange while higher temperatures tend to be
green or blue. Color temperatures are measured in degrees Kelvin
Temperature Source Color
1950 Candlelight Orange
2870 Normal Incandescent Orange
3200 Most Photo or TV Lights Orange
3400 Some Photo Lamps Orange
3500-4000 Fluorescent Lamps Green
5500 Midday Sunlight Blue
                                            (R.Inman And G.Smith, 1996)
The eye "remembers" how things are supposed to look and interprets color
accordingly, regardless of the color temperature of lighting sources. A white
sheet of paper seems white whether viewed under an incandescent lamp or
Sunlight. The eye can even adjust for "correct color" when two light sources of different colors are present in the same scene. Sunlight streaming into a
room which is also lit by incandescent lamps doesn't make objects it strikes
appear bluish.