The longest distance in my house is 6.46 meters so I use this for throwers.
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Reading X 6.46 X 6.46 = Candela/CD.
Throw = Square Root of 4 X CD, all in meters.
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Same answers as above.
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Presumably you have to do this test in complete darkness?
It’s annoying that there’s no mode in biscotti that contains both 50% and 100%, then it would be easier to tell if there’s a perceivable difference.
Some lights might have regulated high and FET-driven “turbo” where the diff is about 2:1.
Switching back’n’forth gives a little hint of extra brightness, but nowhere near “omgwtf, that’s twice as bright!!!”.
Even with my Q8, I was expecting 5000lm (vs about 1000lm of my other lights) to be like daylight in the backyard, but it wasn’t. Bit of a letdown.
Brighter? Sure, but not “night’n’day bright” as you might expect.
Ok after testing in the woods in the dark, there’s definitely a noticeable difference between 50% and 100% but obviously it’s nowhere near twice as bright.
That’s very good news, but nowhere near being great news.
Over the few or so years, I spoiled myself as to what I subjectively considered to be very bright. As long as I was willing to migrate to larger lights. And that's exactly what I did. The first thing I considered to be very bright was me. Then I was dethroned by the Tru Value Rayz 1000 Lumen 9 x AA. Then that was dethroned by the Four-Sevens MMU-X3, 1,600 lumens. That was no longer very bright when the Niwalker MM15 5,233 lumens lit up my life.
Next, Noctigon Meteor M43vn 12 x XP-L 8,400 lumens.
Next, TN36UTvn 13,400 lumens.
Next, a lot more lux with X65vn with 11,500 well-tempered lumens.
Next, Acebeam X45vn muchly boosted to 25,000 lumens.
Next, Imalent R90TS 36,000 lumens. Next, Imalent MS18 100,000 L-words.
10,000 small white room ceiling bounce lumens is a round number for the cutoff for what looks very bright to my 61 year old, self-spoiled rotten eyes.
Outdoors, more throw with less flood looks brighter per given lumens; to me, anyway.
D4V2 W2, EC03 50.2, X50 and BLF GT94 are on my front four bright burners today. Tomorrow will be FW4a W2, FT02S 50.2, MS06 and HK90 to brighten up my life.
D18, KR1, MT07, MT05, NSX53, FW21pro90, E4K, MS03, TM9K and many others: My life is noticeably brighter with flashlights.
My eyes glaze over at the mix of many factors in determining lumens output (or perceived lux). Not only does the nature of how emitter is hosted, but also selected emitter tint, the battery performance+charge level, and then the selected target range for illumination. Then it all gets so subjectively considered with the human eye, where the brain “adjusts” what the eye is capturing.
As Matt Smith loves to say… Good lux! 
