flashlight output confusion

So, I did some VERY informal testing tonight with my brother. I compared
3 2-mode flashlights:

Surefire E2DL 200 lumens on high, 5 lumens on low
Terralux TLF-3C2AAEX 220 lumens on high, 100 lumens on low
NiteCore EZ-123 180 lumens on high, 20 lumens on low

Comparing all of these on high, they all looked VERY similar, as I expected.
REALLY bright, all comparable.... The shocker came when I tested them on
low... The supposedly 5 lumen surefire was by far the brightest... followed
by the 20 lumen nitecore, and finally followed by the supposedly 100 lumen
terralux... Has anyone tested the actual light output of these on low? Why
is there such a disparity in apparent brightness and manufacturer rating?
Why does a ?5? lumen light look so much brighter than a ?100? lumen light?!

Thanks for any help anyone can provide...

Sam

How did you measure the overall brightness? A ceiling bounce test?

If you were judging by the intensity of the central beam, i.e., the "throw," you were not measuring overall brightness.

what is typed in description, is typed in description ...

better to have the lights run for 10 mins, then measure current draw at battery.
Compare currents measured.
... only way to roughly guess possible brightness
(because You know number and kind of batts and current draw from them. Thats given info, not some typo that can be correct, wrong, old, a joke, ...)

sambeaux2249 said:

Why
is there such a disparity in apparent brightness and manufacturer rating?
Why does a ?5? lumen light look so much brighter than a ?100? lumen light?!

Click to expand...

There are a couple of reasons:

The low specification is often wrong (I know this from my review, where I measure all settings).

The low will increase on some lights, with higher voltage batteries, i.e. CR123 and especially LiIon might have a much higher output.

Comparing output from lights requires a ceiling bounce or light box, just looking at the beam can be very misleading.


When I tested the Nitecore EZ 123, the difference between high and low was 8 times. I have not tested the other lights.