Q: The lighting of Hi-pressure Sodium lamp looks darker than that of UCD Lighting.
Why is the Lux reading of HPS surprisingly higher than UCD’s sometimes?
The Lux is the unit of illuminance in international system of Units (SI). It has defined in terms of lumens per meter square (lm/m2) and to measure at 555 nano-meter only. Therefore HPS having strong spectrum at 555nm only may have higher Lux reading.
