Help... teach the newbie

kramer5150

Flashaholic
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Sep 6, 2005
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Palo Alto, CA
Can someone please help me understand specs and definitions...

So,
Lumens is the total light output from the torch.
Lux (or candlepower) is the intensity of the light at a given distance.

When manufacturers state "Lux=XXX", at what distance are they rating their products? is there an ISO or standard fixed distance?

What is the conversion ratio between Lux and candlepower?

I dont understand reflectors and their ability to "throw" light... Why do large reflectors throw farther than small ones? Theoretically if you have a small reflector in close proximity to the source... why would that be less effective than a large reflector that catches light farther away from the source?

:thinking::thinking::thinking:
 

Gunner12

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Dec 18, 2006
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Bay Area, CA
Well, most don't specify what distance their Lux numbers are measured at and there is no specification. On CPF, most of the distances that reviewers measure Lux at is specified.

There is no conversion between Lux and candlepower that I know of.

Well, a bigger reflector collects and projects more of the light into the beam then a smaller one. Same with a deeper one. Reflector geometry is also important. A smaller correctly made reflector can out throw(presuming equal output) a larger lesser reflector. The ratio of reflector size and emitting area is also important. A smaller light source with a small reflector will throw more then a same sized reflector with a larger light source(presuming same output).

If you had a real point source of light, then reflector size wouldn't matter.
 
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KeyGrip

Flashlight Enthusiast
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Sep 18, 2006
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Back in Santa Cruz
You've got the basics. Now get out while you still have money. Really, what Jeff said. And don't try to escape by nighttime, either.
 

kramer5150

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Sep 6, 2005
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Palo Alto, CA
Too late... hook line sinker. I have had a 4D and minimag for around 10 years, ~15 years ago my brother gave me a fulton GI and a coleman spotlight. So I guess I've always been hooked to some degree.
 

Katdaddy

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Feb 26, 2007
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318
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South Mississippi
Too late... hook line sinker. I have had a 4D and minimag for around 10 years, ~15 years ago my brother gave me a fulton GI and a coleman spotlight. So I guess I've always been hooked to some degree.
Oh you ain't seen nothing yet!!!:shakehead
Wait till you've been around here for a few months.:welcome:
 
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