Off topic: Watts vs. Lumens

[Bucket Head]

What is the difference between a watt and a lumen? They used to rate some L.E.D. lights with watts and now all I see on flashlights and the like are lumens. I guess the real question here should be how many lumens to a watt? I have several flashlights and headband-type lights that are rated at 1 and 3 watts. They are bright and I like them, but I don't know what their lumen equivalent would be.

Steve

[Thompson's Tree Farm]

Watts measures energy consumption and lumen measures light output. There is no equivalency rating but in general, as the energy consumption goes up, so does the amount of light. I know this doesn't help you do a conversion.....

[maple flats]

I think a lumen is one candle power of illumination. If you have the same type of bulb, the lumens rise as wattage climbs. Lumens allow you to compare illumination across differing types (and thus efficiencies) of bulbs. That is why they compare compact flourescents to incandescent for illumination. However you will find often that the the compares are somewhat loose. In the CF bulbs I find another good comparison is the temperature rating of the light which refers to how white the light is, the whiter the light the brighter is seems even within the same wattage. This is why you will see 2 bulbs lit and one is yellowish in color while the other is much whiter light. The higher temperature rating the whiter. These temp. ratings refer to what temperature a flame or molten object is that gives off that whiteness of light. I personally like 4500 & 5500 temp equivalents for reading or seeing detail, but a lower rating in some other applications. This also compares with some of the hedlight bulbs you see now, some are a hotter bulb, thus illuminating farther in most cases.

[Dennis H.]

I think what is happening is since wattage on packaging doesn't tell you how bright a light is anymore that they are putting the lumens on the package to give you something to go by. It wouldn't surprise me that the companies are required to put the lumens on the package just like the food manufactures are required to put a notice on the package for Trans Fat.

The biggest thing with temp of a light is how colors are rendered under the light.

[Bucket Head]

Yes, I'm familiar with how "hot" a light could be and how it reacts with colors from my college photography schooling. With photography, all lights are ranked as to how close they compare with sunlight. Well, with film that was the case. Digital cameras these days do better with different light sources and brightness of light.

I was looking at L.E.D. lights while Xmas shopping lately and thought I could'nt buy a light like what I have since I have no idea on what the lumens was of my wattage rated lights at home. I'll have to see if I can figure out what my lights are in lumens, or see if there is a temp. rating on them.

Steve

[Dennis H.]

Now that will be a tough one to figure out, all those little lights.

I haven't looked at LED xmas lights yet but I have to imagine that somewhere on the packaging it states the total wattage rating.

[Bucket Head]

No, I'm not trying to figure out the Xmas lights. I was looking at small flashlights and those headband type lights. My father and I use 3watt headband lamps- can't live without them. I was comparing lights recently and none of them had the watt rating on them, just lumens.

Steve