A foot-candle (fc) is a unit of illuminance or light intensity. It is defined as the amount of light that falls on a surface of one square foot from a source of one lumen per square foot.
Foot-candles are used to measure the brightness of light in a variety of settings, including homes, businesses, and outdoor spaces. They are also used in photography and cinematography to measure the amount of light that is available for taking a photo or recording a video.
The amount of foot-candles needed in a particular setting depends on the activity that is being performed. For example, a home office may only need a few foot-candles, while a factory floor may need hundreds or even thousands of foot-candles.
Foot-candles can be measured using a variety of devices, including light meters and photographic light meters.
History of foot-candle
The foot-candle was first defined in the early 1800s by the British physicist Thomas Young. Young defined the foot-candle as the amount of light that falls on a surface of one square foot from a source of one candle placed one foot away.
The foot-candle was adopted as the standard unit of illuminance in the United States in 1893. It remains the standard unit of illuminance in the United States and a number of other countries.
Advantages of foot-candle
Foot-candles are a simple and easy-to-understand unit of illuminance. They are also relatively easy to measure.
Disadvantages of foot-candle
Foot-candles are not a metric unit. They are also not a very precise unit of illuminance.
Alternatives to foot-candle
The lux is the metric unit of illuminance. It is defined as the amount of light that falls on a surface of one square meter from a source of one lumen per square meter.
The lux is more precise than the foot-candle and is becoming increasingly adopted as the standard unit of illuminance around the world.
Conclusion
The foot-candle is a unit of illuminance that is still used in some parts of the world. It is a simple and easy-to-understand unit, but it is not a metric unit and is not as precise as the lux.thumb_upthumb_downuploadGoogle itmore_vert