How does 12000 mcd led work light compare to a 500 watt halogen worklight?
That depends on the LED and the halogen lamp. The units mcd (millicandela) and W (Watt) do not denote the same type of measurement. Watt is the unit of measurement for radiant flux, which is the energy radiated by the light source per unit of time. This light may be radiated in ANY direction. Candela (or millicandela = 1/1000th candela) is the unit of measurement for luminous intensity, which is the amount of energy (of the total energy available as radiant flux) radiated by the source for a unit solid angle, in a certain direction. Synonymous to luminous intensity is radiant intensity, the unit of which is Watt/sr (Watt per steradian which we can clearly see is not the same as Watt). 1 Watt/sr = 683cd = 683000 mcd. This means that you can have two light sources with the same available radiant flux (say 500 Watt), but one may radiate light in a narrow beam of only 1steradian while the other source radiates in a wide solid angle of 3sr. The first source will then have a radiant intensit
