# Testing extreme solutions.



## Barbarin (Mar 27, 2017)

As some of you already know I have been quite involved into caving and cave diving during many years. For this reason I always focused my research and activity on reliable lights that could be used for demanding applications. One of the most demanding down there is photography and video, as the amout of light needed to get decent results is many times what our eyes need, specially for video as for photography can be solved using flashes and long exposures. 

But of video you need great flux, and this does not come without the cost of weight and bulk which are not welcome on those activities. So I decided to make something as a super sports car of portable lighting devices; light, powerful, and pocket sized. Result? 2000 lm, 150 gr, 40 minutes with a single Li-ION 18650 






















Technically is an MCPCB with one AMC7135 linear regulator for every three 0,5 Watt 2835 LED, son theoretically it would be underdriven to 66% of their maximum capacity. But the internal resistance of the batteries here will keep the current on 2980 mA and 3,89 V in T=0. This means 11,59 Watts, so hardly 50% of the max current, as some of the power is being used on the regulators. The lumen output is, checked with first class equipment, 2000 lm.Yes, that means a 172 lm/watt efficiency. Not just that. Ra is over 80 (most flashlights won't reach even 70) and color temperature is 4000ºK. 
Those are not normal LEDs, and I got them because I buy millions and the manufacturer is willing to provide me some "superclass" ones.

The results are with a single battery. If we increase the number of batteries the current will be higher, but in this case I was studying the MVP. 






As you can see at the end of 40 minutes the output is still 55% of the initial output. I didnt wanted to perform a total runtime test. Anyway, here I hope you will find some useful information for your projects. 

The two small microprocessor heatsinks you can see are more than enough to keep the temperature under 45ºC at 21ºC ambient temperature, no air flow. If you look at the line of the TºK you will see that it is very stable, a clear sign that heat is not an issue. 

Regards, 

Javier


----------



## ncgrass (Mar 27, 2017)

I'm not 100% what all the numbers mean, but that's some awesome run time and output. Are the LEDs bare or covered? And how will you mount it for photography/filming?


----------



## Barbarin (Mar 27, 2017)

They are kind of bare. But in fact you can soak them in salt water because they are nanocoated in parylene. 
I added a "GoPro" male adapter, so is compatible with million accessories.


----------



## ncgrass (Mar 28, 2017)

Huh, very cool. Good idea with the GoPro mount too. How have you results with your camera been so far? Looks like a really efficient way of getting that extra light that's sometimes needed.


----------



## Barbarin (Mar 28, 2017)

ncgrass said:


> Huh, very cool. Good idea with the GoPro mount too. How have you results with your camera been so far? Looks like a really efficient way of getting that extra light that's sometimes needed.



I dont have a GoPro around, but a Canon S120... which is better when it comes to low light conditions. But anyway, I will get my hand on one in two weeks or so. The usual illuminators they do sell for the GoPro can't make more than 500 lm. So, this is a giant step forward. 

Javier


----------



## ncgrass (Mar 28, 2017)

I'd be interested in seeing the results with a GoPro for sure. If you end up getting around to it, please update the thread =)


----------



## Barbarin (Mar 28, 2017)

ncgrass said:


> I'd be interested in seeing the results with a GoPro for sure. If you end up getting around to it, please update the thread =)


Does a test with an IPhone 7 have any interest for you?Javier


----------



## ncgrass (Mar 28, 2017)

Absolutely. I like the idea. Very compact, lightweight and looooooong run time.


----------

