You really couldn't beat that price! The pair of red/black Ultrafire cells I just ordered cost about the same as two of these.
Down to about 23% - 294 lux / 65 lumens
Stopped the test at 14 microamps as was concerned about the cell voltage. The cell was down to 3V which is low enough for an 18650. Runtime at this point was 2 hours and 10 minutes. Generating graphs now.
Medium runtime started - 586 lux / 130 lumens
Runtime done with a grey unprotected Trustfire "2500mAh" 18650.
http://www.dealextreme.com/details.dx/sku.19770
Oops I see I forgot to put in the runtime percentage. Conventionally runtime is to 50%
Not bad runtime there, thanks for doing that Don.
I had mine running for an hour today just to see how hot it got and i was surprised that seeing how bright it is it doesn't get that hot..
Are everyone else's like that? i was easily able to hold mine after an hour on full power without any discomfort.
Charles
Still at 67% after 3 hours - 2500mAh 18650 medium
Down to 420 lux / 93 lumens
Heat: Because I don't disturb it during runtimes I couldn't say. But I've not noticed it getting hot in use. When I ran it last night to see how the brightness fared, the whole thing was pretty warm after sitting on the desk for half an hour, but wan't in the hand-burner category.
You can test it with 2xCR123A?
I not say do the complete test, but see if it is brighter at first moments with these batteries?
With your permission, I stole the plot of data for our forum. ;)
Great job (as usual) Don.
Feel free to take any of the data. Most of it probably won't need translation and anyone is welcome to use it for any non-commercial purpose.
I'm happy to try it with 2xCR123A. I'll be interested to see how it gets on.
Since it is doing a runtime just now that looks like it is going to take a while, it won't be tonight - I only have one lightbox.
Ok take your time and thanks.
I use it with the CR123A, but I've been in the car for very specific uses (so far) and mine no longer has the original driver or led.
Just be careful with the 2xCR123A. I do not know the efficiency of the driver but it might warm up considerably more at 6v in continuous use.
6 hours 30 minutes on medium 98 lux / 22 lumens. Not bad going. Official runtime to 50% around 5 hours. This is quite impressive. Runtime on low should be quite a long time.
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...