Brett,
How are you getting lower amp draw with the LED's ?
Perhaps you don't need as much light ?
They use the same amount of power as properly selected halogens. Same battery weight. Same AC requirements.
Again, LED's are not battery power savers , lumen for lumen.

Maybe the effort in designing and fabing and LED light is more than designing and fabing a good halogen light.
Apples for apples.

Les,
Interesting discussion. I am certainly surprised that halogens are comparable to white LEDs in terms of efficiency. I was just reading that a mini-mag light draws 0.8 watts on fresh batteries, I'll have to find my 1 watt white luxeon star, as I recall it will dimmly light an entire 12X15 ft room when placed up in one corner, I don't believe the same could be said for the mini-mag, but I am going to check. My question to you is, if in fact halogens and LED are basically equivalent why would I want to design a lighting system where I would have to be constantly replacing burned-out bulbs when I could have one that wouldn't, and have the added bonus not having a hot light fixture. I am pretty sure you knowledge of LED technology is rather dated and I'll bet your "properly selected" halogen bulbs are not cheap, however it seems to me, the most versatile and portable lighting system using currently and easily available technology, would probably use both halogen and LED sources together, each for it's strengths. Mark

PS ultimately using hot wires to generate photons is an aging technology all that heat is just wasted energy, LEDs are just begining to find their way into the mainstream as a basic lighting source. the advances in the last couple of years are simply astounding and will continue.

Mark,
I am fairly up to date on LED's. I designed the LED light source for my 35mm film scanner. I also am a bit of a flashlight-a-holic, and have a couple of 1 watt flashlights as well as a 75 watt Xenon short arc, ala Maxabeam.
It surprised me that the halogens are about as efficient as a good white LED.
For a flashlight that gets knocked around a lot, it makes total sense still, plus I like the blue-green light tint my Luxeons give me.
Sure, hot metal wastes a lot of energy in the IR band, but still, they *do* make a lot of usable photons.
It really sucks when old tech, as boring as it is, still does a great job!
One of the big problems with white LEDs is the color unevenness across the field.

Has anyone investigated small cold cathode fluorescent lamps? I know that the normal household 'compact' lamps make probably 2X the light of an LED ( lumens/Watt ) but they are bulky. Maybe the thin long cold cathode ones are better? They are used extensively in laptops. Hmmm, laptops are power critical... and they don't use LED's either!

-Les

Rather than continue with the he said she said heres real world specs of my LED light:

LED Light
Total Wattage Used: 12watts
Light Output: 350fc @ 1 ft
Light Beam Angle: 60 degrees (perfectly even color all the way across the beam)
Operating Temp: 102 degrees physical bulb temp after 1 hr

Please give us link to a halogen bulb that has better specs

Also laptops use fluorescent like bulbs because of what they are lighting up...the screen. The screen needs to be evenly lit from one side to the other. The bulb as the physical characteristics it needs to make that happen. Have you used a micro Kino before?

Les,
I stand corrected! You should checkout the candlepower forums it's all about flashlights, incandescent, LED, whatever at a very high technical level. Mark

Brett,
have you posted a pic of your light? I would love to see it! This thread is inspiring me to mount up my luxeon for use on my 953! Mark

Brett, I'll see what I can dig up.
Are those the specs for the LED garden light that ledtronics sells? Or are you using one of the trailer lights?
Dimensions of your 12 watt light ?
-Les




<<<-- Originally posted by Brett Erskine : Rather than continue with the he said she said heres real world specs of my LED light:

LED Light
Total Wattage Used: 12watts
Light Output: 350fc @ 1 ft
Light Beam Angle: 60 degrees (perfectly even color all the way across the beam)
Operating Temp: 102 degrees physical bulb temp after 1 hr

Please give us link to a halogen bulb that has better specs

Also laptops use fluorescent like bulbs because of what they are lighting up...the screen. The screen needs to be evenly lit from one side to the other. The bulb as the physical characteristics it needs to make that happen. Have you used a micro Kino before? -->>>

Yes. Its their LED work light. 198 LED's. Although I've altered mine in a few ways to make it work better such as using a 14.4V battery source. Heres a link to some pictures of it.

http://www.dvxuser.com/cgi-bin/DVX2/YaBB.pl?board=Links;action=display;num=1071261354;start=135#141

-Brett Erskine

Don't overlook their 400 LED streetlight. Pricey at $750, Qty. 1 but nice.

LEDTronics brought me one of the garden lights to play with. Very nice and very even. If you had a white plastic shower cap to stretch over it, you'd have a great softlight.

A couple of those and a couple of the narrow-beam MR-16's and one would have a great light kit that could run off a battery you could easily hold in your hand. Or use a battery on each lamp and know that they'd run all day if you want.

I'd be interested in making a panel with a mix of 3000 and 6000 Kelvin LEDs so I could switch color temperatures with a, wait for it, Switch!

Brett,
that panel looks pretty darn cool! Mark

Back from the great adventure with the MR16 LEDtronics 42 LED light.

It worked well. Just enough light to lighten the shadows and pop up the color. Ran all weekend on the LiON battery and a 'C'-sized alkaline to get closer to the rated 14 volts.

I ran out of time to machine a housing so I went to Home Depot and purchased one of the strip-light MR-16 fixtures. I removed the entire light head and U-shaped bracket that holds it to the block that contains the transformer and electronics. That gave me a fairly good looking light fixture with a mount for the top of my DSR-300 (which will accept a 1/4-20 bolt on the handle to tie down their studio viewfinder).

The lamp housing cost $19.95 IIRC and accepts the MR-16 LED lamp directly. Then I spliced the wiring from the battery to the wiring that is supplied with the lamp housing and the job was done.

I did spray the white lamp housing with a dark gray enamel so that it looked more like a Real Professional Light.

The light spread was perfect (the MR-16 lamp is the LEDtronics Medium width version) and would light the area covered by my lens on full wide-angle (which isn't very).

Funny thing was people kept telling me my light was on and I was going to run the battery down.

Would I use this again? Yes. I think it might make a fairly good interview light for on-street use. For that I'll make a power cord that will plug onto the built-in light power socket on the DSR-300.

Anyone have a source for a compatible plug?

The Ultimate in White Led lights for your camera
www.litepanels.com

At those prices, not for me.

Me either, but they are way cool. (no pun intended)

you guys should check out the latest LED technology.

http://www.luxeon.com

Up to 120 lumens for each LED!!!!and they are at 5500 K temp AND at 3300 K!!!!