In, this video, I test and review the most powerful LED flashlight that exist on the market right now : the IMALENT DX80,
also known as “The End of Darkness”, producing an insane 32.000 Lumens !
This flashlight contains its own battery pack (4S2P). Its reflector is designed to be both a good thrower (more than 700 meters) and a good flooder (more than 125 degrees) which makes it a good candidate as the most powerful search and rescue (SAR) drone light.
Of course you will not be able to use this on your DJI play toy as you need to carry this 1.2Kg payload with enough endurance for a SAR mission.
So build yourself a serious X8 multicopter with Arducopter !
380 usd and you will need seriously dismantle to power it and control remotely.
Why not buy a 500w led (~50000lm) https://www.ebay.com/itm/Epistar-50W-100W-120W-150W-200W-300W-500W-High-Power-LED-CHIP-White-Light for 90usd and hack together a power supply and lens for another 100usd. Since noise is not an issue on a copter you can use active cooling (or put it under a prop :D) spare a heavy heatsink.
Less cost, more light, more diy fun.
Cost is 200 dollars on Gearbest with quasi permanent coupon code (check chinnature channel to get the coupons).
The idea of using 500w leds is not new and it is actually much more expensive , heavier and less safe/redundant:
It is more expensive because : you need to add, not only the basic LED cost, but a reflector which is crucial (a led without a reflector will not produce a beam of light that is usable at a certain distance or for a certain width), the cost of a led driver (that alone will cost dozens if not close to hundred dollars), a heatsink, a heatsink cooler (fans or water block cooling), a casing and the most of all BATTERIES!! Don’t forget that for 200 dollars you get the DX80 with a LiIon 4S2P battery pack included (just the cost of such battery pack alone is more than 100 dollars).
It is heavier because : the efficiency of LEDs has diminishing returns with its size and power : for the same quantity ol produced lumens, you need more amps for one bigger LED cell than for multiple smaller leds. More amps for more powerful LEDs requires bigger batteries, bigger heatsinks, so more weight.
If you compare the lumens/gram ratio of the DX80 versus an array of 100w leds (you need an array of minimum three 100W leds to get the same lumen output as a DX80 flashlight), the DX80 is a clear winner : ratio of 32 versus ratio of 21 for an assembled LED solution (source : stratus aerial lights, who are producing and selling a solution as you propose)
It is less safe and redundant : when you have of one high power led failing you do not have anymore light…While on the DX80 you have 8 independent LEDs.
It has a much lower lifetime : CREE XHP70 high power leds have a 50.000 hours lifetime. You get reduced lifetime with higher power LEDs.
So using DX80 flashlight or even using multiple DX80 heads (you could discard the individual battery packs and use a bugger single one for mutliple heads) still seems to me to be the best solution.
For example you could achieve 100 000 lumens with three DX80 for a cost of 600 dollars, BATTERY included !!!
The cake is a lie. Although the DX80 is capable to throw 32000lm (actually around 25000lm according to measurements) in turbo max mode. For around 3 minutes then thermal management kicks in and you will have only 7000lm. This is definitely not for SAR. I still think that a a single chip 200-300w led with good active cooling still better if you need continuous high light.
A word on redundancy. High power COB led’s are made from around 100leds connected serial and parallel. So it will never goes dark at once, just loose some of the leds… http://budgetlightforum.com/node/56217
it is indeed a hell of a handheld torch, but for SAR light on a copter it falls behind…
My arguments hold on lumen/weight ratio, total price and safety (assembling 100W LEDs is tricky, protecting it from touching any other metal or carbon surface on a drone, reverse polarity protection and so on). I can partly agree with your redundancy argument to a certain extent for the LED module alone but unfortunately in your DIY solution you’ll introduce a lot a single points of failures and maybe even wiring mistakes/errors, playing with high drain amps circuits.
