I recall discussion of the old Arc AAAs, which drop to moonlight when the battery’s near exhausted. Maker Gransee recommended that if anyone really needed the light to leave it on continuously rather than turning it off and back on later thinking to save the battery — because powering up the driver sucked so much power compared to just keeping the LED glowing.
I am looking at long runtime with a usable amount of light. My Armytek Tiara sits at .4 lumen for an advertised 60 days. The Elf C2 advertises .4 lumen for 200 days. Nice.
I suppose, if in darkness long enough, .1 lumens could seem pretty bright. I guess the litmus test for me is the amount of light I would need to be able to read or navigate in the dark.
Yes, most of the MkIV models have around a 0.07 lumen minimum. That’s been around for the past couple of years. Before that, they used to do 0.01 lumens.
Of my 4 most recent Zebralights (all MkIV versions), the SC600w HI, SC600w Plus, and SC64w HI, all have the 0.07 lumen minimum. My H600Fc has a lower minimum moonlight. It’s not quite as low as the old 0.01 outputs, but it’s nice to see they haven’t completely given up on the really low modes.
IMO, the 0.01 outputs are just too low to be useful. Perhaps usable to some, but not me. Great for run-time contests, though!
I would hazard a guess that actual runtimes vs advertised runtimes are also something that can vary greatly as well? I am pretty new to a lot of this so I am trying to learn all I can.
No it is not hard. Get yourself a 16 dollar luxmeter that reads as low as 0.1 lux, a 4 dollar styrofoam ball, a small piece of alu-tape and some cellotape to close the ball and fix the luxmeter. Two holes with an exacto knife later, and a basic calibration with a known output light, you have a measuring device that measures fairly accurate and repeatable down to 0.005 lumen, and a bit coarser down to 0.002 lumen.
I just received an AAA Manker E02 (Red body) that has a programmable moonlight level with a range of 19!!! different sublumen levels
this is the lowest, it is lower than any light I own except my magnetic rotaries
The above lumen values come from my own tests, I do not rely on mfg specifications.
the E02 actually reads ZERO on my meter (my meter’s lowest reading capability is 0.01, which means the E02 is making less than 0.005 lumens, due to rounding)
When researching a light, I use google image search, to look for reviews with independent output and runtime charts. I especially like reviews by zeroair, he is very thorough, but I did not find an E02 review on his site…
Sorry, I was just referring to the specs. I have the orignal run Ti which I think many of us got for $5 Its my most fav middle of the night bathroom use light!
If something is 0.04lm still does not mean it is directly comparable to another light because of many reasons.
-Almost all the time all these ultra low lumen measurements are incorrect
-Not all LEDs have the same efficiency, one LED mode needs one current for the same lm value, another LED needs another current for the same lm value as the other LED model.
-Not all drivers have the same efficiency, actually ultra low currents are highly inefficient on pretty much all drivers, so extrapolated runtimes which all manufacturers offer are only that.
-Different cells types (chemistry, capacity, self-discharge, etc) offer differ runtimes.
So comparing flashlights based on manufacturer advertisements is as unrealistic as it gets.
I just measured the lowest moon setting of my Manker E02 with 4000K 219C at 0.002 lumen, right at the limit what I can measure. Unfortunately the current drain stays high at 5.56 mA because the MCU is kept awake, so in 6 days your battery is empty (could be 14 years if it was just the led that used current).
These luxmeters use silicon sensors that are as far as I know lineair in their whole range. At least I never noticed alinearity and I also know no sources that say otherwise (I did search for it)