The luminous flux is similar to a quantity of (light) energy, and if you spread it over a larger surface area, the light will become dimmer. For instance, if we say that it is a photo that was shot at 0.5 LUX, it means that we measured 0.5 LUX right where the subject was.
Most light meters you can buy have a ~0.8-inch hemispherical light sensor and have a range of 0.1 to 200,000 for the basic models.įor photography purposes, we can set the sensor right in front of the subject and measure the LUX number at that point. In the context of this site, we mention LUX ( Wikipedia page) as the brightness as measured by a light meter. LUX is a brightness measurement unit that represents the quantity of light (luminous flux, in lumen, explained below) that is received ( illuminance) by a surface and expressed in lumen per square meter, or lm/m 2.
