DESCRIBE MEASUREMENT OF STUDIO LIGHT WITH A LIGHT METER
Describe light meters, their functions, and techniques of using light meters.
Given information and illustrations relating to light meters, their function
and the technique of using a light meter.
Demonstrate competency of the task skills and knowledge by correctly responding
to 70 percent of the multiple-choice test covering descriptions of light
meters, their function, and techniques of using light meters.
Learning Event 1:
DESCRIBE LIGHT METERS, THEIR FUNCTIONS, AND THE TECHNIQUES OF USING A LIGHT
1. In the television studio, it is necessary that we control how much light is
sent to the television camera. There are various ways of controlling the light
but only one accurate way of measuring its brightness. That is with a light
meter (also referred to as an exposure meter).
2. The light or exposure meter measures light intensity or brightness. Light
entering the meter falls upon a light-sensitive surface, usually made of
selenium, which reacts to light generating a small electric current (fig 2-1).
3. The meter is actually a microammeter which measures the current produced.
The microammeter causes a needle to deflect across the face of the meter scale.
The brighter the light, the more current is produced, causing greater
deflection of the needle. The scale that the needle deflects across is often
marked in footcandles and f/stops.
For television studio lighting, the
footcandle scale is the most often used.
4. When using
a light meter, it stands to reason that we are measuring the
amount of light
on a set or event area. In actuality, we may be measuring the
amount of light
falling on the set or the amount of light reflecting off of the
set. These two
methods are called incident and reflected light measurements.