LED throwing power

JJHitt

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Dec 30, 2002
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Houston, TX
I've always wondered how you measure "throw".

If a light has a throw of 50 feet, does that mean the photons fall to ground gasping for breath at 51 feet?

How do measure something as subjective as "bright enough at a distance'?
 

jtice

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May 21, 2003
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Well, thats sorta what "lux" is.
Lux is basically high bright the hotspot is.
Well, the brighter and tighter the hotspot, the further the light will throw. (in most cases)

"Lumens" is the total overall light output. So, you could have alot of lumens, but no throw. IE a flood light. Its putting out alot of light, but its not focused, so it has a low Lux rating.

I dont have the link handy,,, but go look at QuickBeams awsome throw vs. lumens chart.
 

BlindedByTheLite

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[ QUOTE ]
IsaacHayes said:
I'd say the BlasterIII or FT-3C could as it has lux in the 5,000 range...

[/ QUOTE ]
Wayne was getting 8,000 lux on the FT3C with Nimh! /ubbthreads/images/graemlins/grinser2.gif
 

rlhess

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Could we all please switch from lux to candela?

Lux at 1m = candela
footcandles at 1 ft = candela

We're really talking about candela.

But, because of beam shaping and generation issues, it's still a good idea to mention the measuring distance.

Anyway, the L6 puts out about 1500-1600cd (measured at 10') while, for example, the TL3 from Streamlight is about 8500 or more cd, depending on battery condition.

To get some measure of throw, take the square root of the cd output and that will be the distance to 1 fc in feet or 1 lux in meters.

This is an arbitraty cutoff. In very dark surroundings, it will throw farther (or seem to). I find 1 fc in a suburban environment without long periods of dark adaptation is reasonable. Then a 10000cd light will throw 100 feet.

Cheers,

Richard
 

UnknownVT

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Dec 27, 2002
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[ QUOTE ]
Mrd 74 said:
So what is the longest throwing production LED flashlight?

[/ QUOTE ]

I think one with the correct density and aerodynamics can be
thrown further............ /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/grin.gif
 

stockwiz

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Nov 16, 2003
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Brookings, SD
The best optics still don't compare to a large reflector for throwing the beam of an LED, I've come to find that out when finishing modding this 3D mag. I have one of electrolumen's new 3 C cell lights coming and looking forward to testing it.

The 3D mag I modified with a 3 watt luxeon TWAK throws quite a ways using the stock mag reflector.. very tight hotspot. Never actually measured the distance, but it easily lights up the neighbor's house across the street which is 50 feet, and will light up houses noticably bright down the block that I would estimate would be roughly 200 feet from my location. I should do some measurements when I get the time.
 

S4MadMan

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Does a Mr. Bulk "production" count? My Mr. Bulk L3C is a laser beam. /ubbthreads/images/graemlins/grin.gif

mrbulk-l3-02.JPG
 

IsaacHayes

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Jan 30, 2003
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I listed production lights.. Of course modded mags with luxIII's will have lux @ 1m in the 10,000 range...
 

gwbaltzell

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Dec 8, 2003
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StL MO
[ QUOTE ]
UnknownVT said:
[ QUOTE ]
Mrd 74 said:
So what is the longest throwing production LED flashlight?

[/ QUOTE ]

I think one with the correct density and aerodynamics can be
thrown further............ /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]
Thanks ... I've been trying to resist all day!
 
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