Down below 50% but still a lot of light - 617 lux / 137 lumens

FlashPilot wrote:

Looking forward to your review. The MRV's have been my most used 18650 lights since I bought them... and also my least expensive 18650 lights.

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%

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.

XRAYBoY wrote:

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.

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.

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..

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

fishinfool wrote:

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.

XRAYBoY wrote:

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).

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