I was shopping for a flashlight recently, and naturally
noticed a trade-off between size/compactness and brightness.
The devices range up to 500 Lumens.
Human perception is logarithmic. So I wonder, at what
point, measured in Lumens, does apparent brightness
level off? For instance, imagine you're in a dark place,
and you want to blind an adversary. How many Lumens required?
I was shopping for a flashlight recently, and naturally
noticed a trade-off between size/compactness and brightness.
The devices range up to 500 Lumens.
Human perception is logarithmic. So I wonder, at what
point, measured in Lumens, does apparent brightness
level off? For instance, imagine you're in a dark place,
and you want to blind an adversary. How many Lumens required?
Lumens are like watts---they measure the total amount of visible light.
A good 100W incandescent bulb circa 2012 put out 1690 lumens. That's a
whole lot for a flashlight.
For a narrow-angle applications, you care more about lux (lumens/sq
metre). 1000 lux is a nice number for reading a book, but 5000 is better
for an old guy doing close work. ;)
For incapacitating somebody, you're much better off with an 8-D-cell
Maglite, know wha' I mean?
On February 17, Phil Hobbs wrote:
I was shopping for a flashlight recently, and naturally
noticed a trade-off between size/compactness and brightness.
The devices range up to 500 Lumens.
Human perception is logarithmic. So I wonder, at what
point, measured in Lumens, does apparent brightness
level off? For instance, imagine you're in a dark place,
and you want to blind an adversary. How many Lumens required?
Lumens are like watts---they measure the total amount of visible light.
A good 100W incandescent bulb circa 2012 put out 1690 lumens. That's a
whole lot for a flashlight.
For a narrow-angle applications, you care more about lux (lumens/sq
metre). 1000 lux is a nice number for reading a book, but 5000 is better
for an old guy doing close work. ;)
The packages include the FL1 standard, but I don't know how to interpret that. One of the specs displays a light cone, and e.g. '95 ft.' This indicates lux?
Then there's a picture of a light beam reflecting from the floor ...?
For incapacitating somebody, you're much better off with an 8-D-cell
Maglite, know wha' I mean?
One of those police torches - not too convenient for routine carry -
probly nice self-defense gadgets though - "It's a tool, not a weapon, officer!"
--
Rich
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