js
Flashlight Enthusiast
AWR,
Quick note about temperature of the tungsten filament and CCT: they are NOT the same. The CCT is the Correlated Color Temperature, and reflects the "best fit" of an ideal black body radiator to the actual output of the light source. Tungsten is really a "grey" body, so the filament temp and CCT are different by about 80 to 100 K, with CCT being higher than actual temperature.
As for the 65 percent figure, Ginseng is the one who quoted it to me way back when I was first doing the TigerLight Upgrade Thread. So I didn't originate it, but I have verified it over time by doing comparisons of lights with known outputs. It is only a rule of thumb to be sure, but it is one that I will hang my hat on, so to speak. I have found it to be within the measurement error bar of the only optical measuring device I own: my eyes.
A calibrated integrating sphere would be necessary to really test out the rule of thumb in each particular case, and over a wide range of total outputs and lamp types and reflector sizes, and so on. But I'm not about to drop 6 or 8 large on one of those!
Quick note about temperature of the tungsten filament and CCT: they are NOT the same. The CCT is the Correlated Color Temperature, and reflects the "best fit" of an ideal black body radiator to the actual output of the light source. Tungsten is really a "grey" body, so the filament temp and CCT are different by about 80 to 100 K, with CCT being higher than actual temperature.
As for the 65 percent figure, Ginseng is the one who quoted it to me way back when I was first doing the TigerLight Upgrade Thread. So I didn't originate it, but I have verified it over time by doing comparisons of lights with known outputs. It is only a rule of thumb to be sure, but it is one that I will hang my hat on, so to speak. I have found it to be within the measurement error bar of the only optical measuring device I own: my eyes.
A calibrated integrating sphere would be necessary to really test out the rule of thumb in each particular case, and over a wide range of total outputs and lamp types and reflector sizes, and so on. But I'm not about to drop 6 or 8 large on one of those!
