While I’ve been trying to figure out correct light power for standard LED strips I use in interior architecture vizualization, I came across advices to avoid Watts and istead use Lumens to mimick the real-world strips.
So I’ve been trying to use both Luminous Power and Luminance for LED strips (Rectangular lights), and I couldn’t manage to get persistent results.
To troubleshoot, I created two rectangular lights 100 x 100 cm in size, the first one with value of 10000 Lumens, and the other one in with value of 10000 Lumens per square meter.
The result I got was two different light powers, even though both are exactly 1 m2.
Model units are in centimeters.
Scientifically, Lumens per Area is related to the area of the surface the light falls on. for example, in office space, the ideal lighting is 500 Lumens per square meter, (measured at desk height) so If you have 100 square meter in office space, you need (500X100) = 50,000 Lumens of light energy measured in the office.
Generally Light Fixtures are measured in Candles, or Lumens. while measured lighting on a surface is measured in foot candles or Lumens per Sq. Meters.
So if I want to mimic a real-world 1-meter-long and 2-cm-wide LED strip that’s 15 Watts per meter (or 600 Lumens per meter) – how do you think it should be done? Create a Rectangular light in that dimesnion – and assign what power, in which units?
I’d stick to “Lumens” and get the manufacturer’s data. Getting into wattage is dependent on the type of lighting (CFL, LED , Incandescence) all have different Wattage for the same number of lumens.
Also please note that Luminance is not Lumens per Square meter, It is measured as "Candela per square meter [ cd/m2 (= lm/(sr⋅m2))]
