beam combining and efficiency

I'm looking to outfit my friend's boat with headlights and would like to have a combination spot and flood LED. But there are options on the LED type, and the optics. seems most mfrs are using 3W LEDs with parabolic reflectors and a flat lens. But then there are the 5W OSRAMS with the "fisheye" lens (double convex?) and also 10W LEDs and one mfr is using 15W leds shining into a single monsterous parabolic reflector.

I've read a little about light beams and everything says the it's all in the optics with big and round ruling.. I saw this in a test last night running a 0.5W 3015 led bulb in a big 6" handheld incandescent spot 12VDC light (the old handheld started with a 5-12W bulb and had a clamp to carry some sort of mongo 12VDC battery). the 0.5W led didn't throw as much light as the 12W incandessant (not surprised) but it threw a ton of light which I attribute to the mongo optics...

back to the headlights.. I see there are options with round lights and light bars coming with several 3W leds or less but larger LEDs (5, 10, or 15Watts). And the lights with less but larger LEDs are much more expensive for a given amount of total power.

can anyone comment on beam distance (or luminosity) comparing many 3W leds vs fewer but larger leds? what about the 3W crees with parabolic refflectors vs the 5W osrams with fisheye or the cree 10W leds. I'm looking for a combo flood around 72 watts (maybe up to 100w?) which has at least 40W of spot..

:welcome:

hi guys and thanks..

I've looked at the rigid industries lights and while impressive, they are also quite expensive and I think there's too many Chinese lights to consider first for the budget minded folks like me.. I mean it would be nice to buy top quality American product but I generally shop at walmart and get Chinese stuff with walmarts mark up and return policy. buying Chinese direct through ebay is a little more risky but they all overstate their power so ebay then will get behind the sale if the seller doesn't make good. my experience with the Chinese sellers is that they will offer 100% refund when they know they sent you junk otherwise they will offer a % back which probably keeps them at break even. this is not to say that I take advantage of the sellers because I generally ask them how much current their products draw at 12VDC to confirm their power advertisements,.

But come on!!! somebody out there talk to me about big vs small leds!

I'd suggest looking at Cree and Luminous's website and see if they offer a LED that meets your requirements. The new XHP-50 and XHP-70 are the newest and brightest from Cree. The SST-70 and SST-90 are the two currently largest from Luminous.

Companies like Aircraft Spruce sell LED landing and taxiway lights. Most are available in both 12 and 24 volt systems. Trying to piece together a LED, reflector and a water proof housing with some type of vibration cancellation probably will cost you much more than purchasing a turn key system.

Yes, for the boat, I am looking to purchase a turn key system. a 12VDC light made with multiple LEDs sealed for environments and sturdy/shock proof. So in selecting a light, being a budget minded person, I am looking at Chinese manufacture (all our Chinese leds to date,except my underwater lights, have held up great). so no, I don't need to buy leds but I guess I could compare specs but then I'd have to know if these Chinese manufacturers are even using the cree or OSRAM leds!! (is anyone on here actually doing reviews or tests of the Chinese lightbars, some of them are name branded..).

So what kind of lights do we need? high efficiency and rugged and reliable. LEDs!!! We motor offshore often at night riding many hours in the dark. The headlights should allow us to see waves (the ocean is very changeable and also since we sail far offshore, there's changes in topography and then winds change too…). We need to see waves in front and to the sides so we can adjust speed and course in handling the waves as we push our light planing hull over them. It's also critical to see objects in the water that we might hit such as buoys (fish pots and lobster pots),trees and railroad ties or containers or sea turtles.. & I would also like to send a beam far out to search for buoys at night (but we did just get radar which should work). The buoys are mostly reflective which helps far off. I was thinking a pair of combo flood/spot bars 60-120watts. But as I write now thinking perhaps one bar as a combo bar to see everthing for sailing and one aimed as a pencil spot to search or see buoys. I'll switch them independently.
Some LED light designs use less leds and larger reflectors... but why? generally the lights constructed with higher wattage LEDs are more expensive but are they giving you more light per watt (or even the same light per watt)??