How much is it going to cost to run 2 x 250W studio lights?
- Thread starter Phate
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Soldato
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depends pm what your electricity supplier charges
0.5*unit rate for 1kwh
0.5*unit rate for 1kwh
Yet they dont draw 250W continuously. Put a meter on them, run them for a while and then you will know for sure.
Soldato
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Why wont a light continously draw it's rated power?
Because light output in Watts and what they draw aren't directly related.
For example, I have a lamp that states "40w Max" with a 9w power draw.
40w of energy is emitted from the light bulb, but it's not the same as watts in electricity, as 9w is only drawn at the wall.
You have a magic light bulb that creates energy.
Or, assuming you didn't go to Hogwarts, you're mistaken. If you have an energy saving lightbulb then it's likely that it's a 9W bulb (it draws and emits 9W) which has a similar brightness to a 40W incandescent light bulb.
because unless he is trying to melt any subjects, they dont stay on constantly, only when they are told to flash by the camera...
It's not, it uses a filament bulb.
Watts in heat, electricity and light output aren't the same thing.
Watt is a unit for 1 joule of energy per second.
A bulb can't emit more energy than you put into it, regardless of it being a filament bulb.
Soldato
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Don't forget that the balists(sp) depending on bulb type, draw more than 250w. What sort of bulbs are they? If they have a balist check the power rating on it as thats the one that matters.
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I'd assume then that the "40W max" is the maximum output the light will ever reach, in heat and light combined.
If its running at 9W, it'll actually be outputting very little light. Most of the output will be in the form of heat.
Soldato
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The wattage only refers to how much energy is used by the light bulb. light output is measured in lumens. For best efficiency look for the highest lumens per watt, for example some flouresent lights will put out the same amount of lumens with much less energy (watts) consumption (can't remember but think its almost 25%) than an incandesent at the same lumens. Why in the world would you measure light in watts?
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