Just what do people mean by "brightness"?

[Darell]

Re: Just what do people mean by \"brightness\"?

[ QUOTE ]
Roy said:
which do you think will be seen as being brighter, a white light or a cyan light?

[/ QUOTE ]
Roy - I think just about anybody who's done that test will agree with you. Cyan is the blinder. It just dazzles me to the point where I really can't "see" anything but the overload color. Right smack in the middle of human vision wavelength. For this reason, I think that a cyan light would have the best disorienting effect if used as a temporary blinding tool at night.

 

[raggie33]

Re: Just what do people mean by \"brightness\"?

is it brither then white? if i use any color then white i cant see too good for some reason

 

[brightnorm]

Re: Just what do people mean by \"brightness\"?

This site discusses some of these isssues. LEDs are further down the page.

LED "BRIGHTNESS"

Brightnorm

 

[kongfuchicken]

Re: Just what do people mean by \"brightness\"?

When testing my flashlights, I use my TLOFSA, my tactical luminosity output feedback sensor array, or in other words, my little sister and her buddies /ubbthreads/images/graemlins/grin.gif
Tell them to stand toghether, then fire away on the group.
"Ow! Quit it!" means arround 3000lux
"Hey! I'm telling mom!" means arround 6000lux
"Quit it! Fine, you can have your stupid notebook back!" means well above the 8000lux /ubbthreads/images/graemlins/grin.gif

They still need calibration since I don't have any extremely bright lights but, I find the result to be generally accurate. /ubbthreads/images/graemlins/tongue.gif ...plus they get out of my hair. /ubbthreads/images/graemlins/nana.gif

 

[brightnorm]

Re: Just what do people mean by \"brightness\"?

[ QUOTE ]
kongfuchicken said:
When testing my flashlights, I use my TLOFSA, my tactical luminosity output feedback sensor array, or in other words, my little sister and her buddies ...

[/ QUOTE ]

In a few years you're going to make some optometrist very happy. /ubbthreads/images/graemlins/grin.gif

Brightnorm

 

[PeLu]

Re: Just what do people mean by \"brightness\"?

[ QUOTE ]
which do you think will be seen as being brighter, a white light or a cyan light?

[/ QUOTE ]
What is heavier, one kg feather or one kg lead? .-)

As mentioned zillion times, the lumen, lux, candela units include already the different wavelengths.

But there are some variations:
1. These are defined for a 'standard' person. You may be different from that. No big difference unless you are colour blind.
2. You are testing at low light levels in the mesoptic range.
3. The object you are looking at with your light is not white.
4. The psychological factor: Usually a pretty big one. You see what you expect or want. Often used for optical tricks.

I'm shure there are more points to add to this list....

Of course one kg lead is heavier, you can tell ist easily by dropping the lead and the feathers on your foot.

 

[markdi]

Re: Just what do people mean by \"brightness\"?

hammer the Kg of lead into very thin sheets
then it will be aslight as a Kg of feathers