all that math im lost lol
This is a discussion on Formula to convert Lumens to Candle Power? within the Related Gear & Equipment forums, part of the Defensive Carry Discussions category; "Holy smokes it's a flashlight turn it on shine in your eyes which one blinds you more." Simple...very simple....
"Holy smokes it's a flashlight turn it on shine in your eyes which one blinds you more."
Liberty Over Tyranny Μολὼν λαβέ
Others have explained it well, candlepowers is the meassure of the center spot brigthness and lumens is the overall brigthness put out by the source.
So to make it more interesting we can take lights with tremendous candlepowers output and compare it with the more sedate lumens figures.
Beamshots coming from 43 yards away, camera at 15 yards from target.
Here are the lights,from left to right, Surefire M-6, Ultra Stinger, Magcharger and my red MAG 951 II (this time with the 3 plastic battery carriers for 951 lumens)
Magcharger, 40,000 candlepowers, 200 lumens
Ultra Stinger, 75,000 candlepowers, 290 lumens
Surefire M-6 (500 lumens) six 123's for 20 minutes run
MAG 951 II (951 lumens, 45 minutes run time, rechargeable)
I'm a lighting designer...
Candlepower is focused brightness (directional beam)
Lumens are unfocused brightness (omni-directional beam)
They are not convertable (apple and oranges kind of thing)
Since, for all practical purposes, we use a flashlight in directional beam mode, lumen measurements are virtually worthless.... so are watts measurements.
Note: I have put this into practicable laymans terms, so if there are any lighting engineers in here... back off.
Hope this helps... and this is my first post... joined today.
http://www.theledlight.com/lumens.htmlCandlepower is a rating of light output at the source, using English measurements.
Foot-candles are a measurement of light at an illuminated object.
Lumens are a metric equivalent to foot-candles in that they are measured at an object you want to illuminate.
Divide the number of lumens you have produced, or are capable of producing, by 12.57 and you get the candlepower equivalent of that light source.
Very Good information posted here. Thanks.
Well, with all that said I'd guess the best way to compair LED with conventional flashlights (one to another) would be to get one of each, turn out the lights and just simply try them out.
Just a bummer that you have to buy both first to do this.
For God, Family and Country!
Lumens help know overall output. In a power outage, I use a flashlight or two sitting on thier tailcaps pointed at the ceiling. Pretty practical purpose where lumens is more important than candlepower.
L=C/0.07958 and C= L (0.07958)
...chance favors the prepared mind. Louis Pasteur (he did that milk thing.)