7 hours. 67 lux / 15 lumens though I'd have thought it was a bit more. Time to stop before I over discharge the cell. Cell down to 2.9V
It had just been runnning on medium for seven hours so the pill was slightly warm before the start of the test. IT wasn't any warmer at the end of the test. But then it wasn't any brighter than it was with an 18650 anyway.
Here's a graph of the output for the first minute.
| Time | Lux | Lumens |
| Switch-on | 1409 | 313 |
| 30 seconds | 1289 | 286 |
| 1 minute | 1178 | 261 |
Long. At least long by my standards ;)
Still producing usable light at 7.5 hours.
Low runtime starting. Back some time tomorrow. Initial output 110 lux / 24 lumens
4 Seconds ISO 80
The tree is 17m / 50' away. The tree top is around 21m / 65' away
Control
High
High Treetop
Medium
Medium Treetop
Low
Low Treetop
102 lux / 23 lumens. Or basically next to no drop. It started out at 110 lux / 24 lumens
I fully expect this one to be going at lunchtime tomorrow - it is just shy of midnight here.
78% brightness 84 lux / 19 lumens
15 hours 80 lux / 18 lumens 73%
20 hours and still going strong. 77 lux / 17 lumens. Looks like it will make a day..
Thanks for all the hard work Don. I really do enjoy these light, as do all the others I have given them to. Do you have a data logging light meter to record your findings or do you do it the old fashioned way? My hat is off to you if you have to hang out all day with a stopwatch, pad and pencil. ;)
Is there a thread where you explain your reporting process? Fun stuff!
I don't think there is a thread on it. I'll do one soon. It certainly isn't manual - the lux measurements are, the output over time ones certainly aren't. I actually have two cheap datalogging meters though I need to use two PCs to get both of them running - the software that came with them doesn't seem to let me use more than one meter at a time. I run two copies of it, both of them see the same meter. Annoying...
23 hours. Still going strong
Still 77 lux still around 17 lumens...
24 hours
Still providing light - wonder how long it'll go on doing so?
73 lux / 16 lumens
25 hours
73 lux / 16 lumens
You're squeezing the efficiency of the LED now in low.
I can only imagine the runtime in low with a couple of good CR123A (1400mAh each), being able down the voltage until to throw them.
Almost eternal.
Courage ... can not be much longer (or not).
Hey Don, when doing these kinds of tests, do you turn them off after a while because of the heat produced? Do you leave them on during the whole runtime test test period? Just curious. Thanks.
On high I stick a fan on them. I own quite a lot of fans from my mad overclocking days.
I will touch the light occasionally to see if it is getting silly hot. The MRV never has.
I don't expect it to still be giving light in the morning - 8 hours from now when I have to go to work again. But maybe it will.
And it is an unprotected 18650 so i hope I am not killing a cell.
However a 16 lumen (25.5 hours) thrower is not the most useful light in the world - a flood light would be much more useful at that light level. I am wondering how long it will stay lit for though - I will keep it running till it goes out. I thought it would give up about 10 hours ago.
26 hours. Still going at much the same level
72 lux / 16 lumens
Don have measured the temperature on the head and body?
And this is with a freshly charged 18650 with the MRV on low right?
Very impressive!