Is a 3 AA 1 watt going to put out more light than a 1 AA 1 watt?

[BamAlmighty]

I'm new to the whole LED flashlight thing so I don't know what to expect with my units.

I have a streamlight HAZ-LO headlamp with a 1 watt Luxeon that uses 3 AA and a River Rock 1 watt Luxeon that uses 1 AA.

Compared to the Streamlight, the River Rock's beam looks so DIM. I know the size of the reflector makes a difference, but the Streamlight looks nice and intense while the River Rock's looks dull. Being they're both 1 watts, shouldn't the River Rock have a similar intense spot?

Or does being powered by only 1 AA compared to 3 AAs makes a difference?

 

[Marduke]

Watts mean little to nothing. Lumens is the true measure of output. An old 3watt Luxeon powered by 4 D cells can be dimmer than a modern 1 watt Cree powered by a single AAA for example (runtime is another matter entirely though)

:welcome:

Sit down, and have a nice read
http://www.candlepowerforums.com/vb/showthread.php?t=172991

 

[mdocod]

are you SURE they are both Luxeon? I was under the impression that many RiverRock products were using some other brand of LED that isn't quite so hot...

you are thinking WATTAGE RATINGS, start thinking efficiency and true power consumption and you will understand what is going on...

Keep in mind that most flashlight manufactures "rate" their LEDs incorrectly... they will list "wattage" on the package even though it doesn't even operate close to the wattage listed, also very common is exaggerated lumen claims. Other times they will rated consumed wattage rather than the actual wattage at the LED, which for a 1AA will be higher than a 3AA because it wastes some energy to do the voltage step-up required to drive the LED.....

However.. In the end, if you take 2 equal LEDs, like say 2 of the same bin LuxI LEDs, and drive them both at ~350mA, and run one from a 3AA power source and the other from a 1AA power source, they will both be equally bright but the 3AA light will run ~3X longer (probably more since batteries deliver more capacity under lighter loads)

 

[BamAlmighty]

Well the River Rock claims 42 Lums, while the Streamlight claims 34 Lums.

And the Streamlight smokes the River Rock by at least twice the lums. It's obvious River Rock exagerated their claims, but I was expected a brighter light.

 

[Marduke]

Beam distribution makes a huge difference also. A light which concentrates the beam in a small area can seem vastly brighter than a light which spreads it's beam out over a large area, even if the first light is actually much dimmer in reality.

 

[MikeLip]

Are we talking real watts or marketing watts? Real watts are what is really being fed to the emitter and, as other have pointed out, are only loosely related to beam brightness and throw.

Marketing watts are generally "the most the emitter CAN put out, assuming an infinite heatsink and liquid nitrogen cooling". A 5 Watt capable LED could be being driven at 1/2 watt, and some makers will still call the light a 5 watt light.

This is like vacuum cleaner horsepower - I've seem some rated at 20 horses. That's about 15,000W! To get that from a standard 115V receptacle would require over 180 amps (counting power factor). Yet these things plug into a standard wall outlet.

Watts don't matter a lot. Lumens do. More correctly, lumens out the front count. And manufacturers are all over the map on how they represent that. Surefire tells you what the flashlight is actually putting out, generally on average, not at peak, on fresh batteries! Most other makers are rather, umm, optimistic in their claims.