A light meter, or exposure meter, is an instrument used to measure the amount of light in the environment. Light meters are most commonly used by photographers. Typically, the information provided by the meter expsoure used by the photographer to determine the exposure time for their pictures.
Light meter will calculate the velocity of your photographic film, shutter speed and aperture settings. It will use this information to calculate exposure settings recommended for your photos. Knowing how to use a light sensor and to interpret the output is an important skill for any photographer to master.
There are two main types of light meters available on the market today: reflected-expsoure and incident-light meter. Reflected light meter measures the amount of light reflected by the scene to be photographed. Light meter used in the camera light meter.
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As reflected light meters are calibrated only to determine the exposure setting for the average scene, they can be confused with a complex scene or atypical. In an unusual scene with the dominant colour of the light or specular highlights, a reflected-light meter will give incorrect readings and will not provide an accurate exposure setting.
Incident-expsoure meter, on the other hand, measures the amount of light on the subject quarrel. They do so by way of ball-shaped light sensor where the photographer by the subject. In this way, the reflectivity of the subject is not to confuse the sensor and is able to provide photographers with an accurate light reading.