DIY LED Lamp Questions

[greyroot]

So I recently spent a bunch of time reading dozens of posts about building DIY LED lights that are battery powered, and it inspired me to finally try my hand at developing some DIY gear. Unfortunately it seems like there are a few key things that worry me.


Where I'm at:
- I've ordered these LED's as they seem to be warm (5100k) for their brightness (23,000mcd) http://www.pcboard.ca/shop/shopexd.asp?id=166
- I also found this calculator http://led.linear1.org/led.wiz for resistors.


What I need to know:
- I wanted to use a Lithium-ion battery from a camera or something similar but theres a few things about them I find difficult to wrap my head around. I hear they are not good for high drain situations, but I don't know how thats rated. I'm guessing with my setup I'll have about 1amp of drain (200mA*52 lights). There are often more than 2 leads from the battery, but only + and - are labeled. What are the extras? I hear there are also dangers in charging them manually, but is there any danger if draining them the wrong way without some sort of double checking sensors or something?
- Do I need some way of regulating the power or would the resistors be sufficient for power management? I was reading that rechargable batteries have variation in the power that needs to be regulated in order to not damage the LED's.


Any other tips are very welcome! I'll let you guys know how the colour of the LED's is and show any stuff I make as the project progresses.

[infurno]

I am interested in this project too. I have been looking for LEDs but having trouble locating something of the right color temperature, angle, and CRI.

For batteries I would suggest here:
http://www.batteryspace.com/

[imager]

I also tried the LEDs from them, but used the their WC241-06 (http://www.pcboard.ca/shop/shopexd.asp?id=145) model Seems to be cooler and I think they are under ated at 15,000mcd as they produce a very bright and wider display.

To hold the LEDs, I decided on the LED Spotlight (http://www.pcboard.ca/shop/shopexd.asp?id=187) which held 24 LEDs. Total current draw was only .16A (160mA), so it is very battery friendly.

Tried the led.wiz calculatr and I was having problems with it in FireFox, but used this calculator there instead. http://www.pcboard.ca/kits/led_notes/

YMMV

[armisiano]

Being a big fan of DIY I'm sorry I can't really help too much, but, dude...


Where I'm at:
- I've ordered these LED's as they seem to be warm (5100k) for their brightness (23,000mcd) http://www.pcboard.ca/shop/shopexd.asp?id=166
- I also found this calculator http://led.linear1.org/led.wiz for resistors.

...I can help by suggesting the phrase "Where I am".

Sorry. Stickler with English.

[sek0910]

well, it is irrelevant to me where he is (I don't care what city he lives in).
I'm more interested in where he's at in his endeavor to build DIY LED gear.

[armisiano]

well, it is irrelevant to me where he is (I don't care what city he lives in).
I'm more interested in where he's at in his endeavor to build DIY LED gear.

Wow. Thanks for the support. lol

[astigmatic]

wow, this is going to be a cool diy project, don't forget to take lots of howto pics:)



Wow. Thanks for the support. lol


Two spaces! Two spaces after periods, and capitalize that "lol"! Lolz, i'z be a punctuation sticklerz. Well not really.



edit: ^^^ wah?! It's the forum that has been screwing up the punctuation!!! There seems to be a major malfunction in the matrix.

[Gary]

You may want to consider these:

http://cgi.ebay.com/MR16-CREE-Equi-LED-WHITE-or-WARM-160-120-lumen-12V_W0QQitemZ190291105415QQihZ009QQcategoryZ20706Q QtcZphotoQQcmdZViewItem

Even though it's an Ebay site the light is the reference. I built a light using 11 of these and it's quite powerful. It's also much easier when you have 3 leds in a housing. I use 12 volt as my source. Cree is the best quality and the most powerful.
Gary

[msousa]

How do you deal with flicker?

[Richard Crowley]

How do you deal with flicker?

What flicker?
Typically LEDs are run on DC and have no flicker at all.
Sometimes they are run on "chopped" DC to control brightness, current, etc. But the circuits normally used run at hundreds or thousands of Hz. The only way you would see any flicker is if you were shooting ultra-high speed (thousands of frames per second).

[Pat Hughes]

The ideal led light. Designed and built it from scratch. Not easy to make and not cheap in materials.Only best components used, solid aluminum frame. Super bright, 4500K neutral white, 110 degree horiz. beam, no hotspots, with or without battery plate, runs from 7.2 - 18 V DC., makes other leds look like a candle. Just showing what I made and is possible. Sorry, I cannot promote or sell these here.

[zakart]

i just bought a grow light that has 225 leds and it is 1'x1' and it only cost $35 so im going to try and make that into a Lite Panel 1x1 type of a light ill let u know how it goes

[Richard Crowley]

i just bought a grow light that has 225 leds and it is 1'x1' and it only cost $35 so im going to try and make that into a Lite Panel 1x1 type of a light ill let u know how it goes

Can you share the source with us? I am experimenting with an LED version of an outside lamp (the kind they use for architectural lighting). It has around the same number of LEDs, but cost several times what you are telling us about.

[Richard Crowley]

The ideal led light. Designed and built it from scratch. Not easy to make and not cheap in materials.Only best components used, solid aluminum frame. Super bright, 4500K neutral white, 110 degree horiz. beam, no hotspots, with or without battery plate, runs from 7.2 - 18 V DC., makes other leds look like a candle. Just showing what I made and is possible. Sorry, I cannot promote or sell these here.

It looks terrific! First-class! What kind of battery life do you get? Is that a dimming knob on the side? What circuit did you use?

[capt chuck]

I'll have about 1amp of drain (200mA*52 lights)

Do you have a typo here, it looks like 10Amps to me.

1 Amp I think would be ok for most camcorder bats, but 10 is a pretty large load.

And you do have to be careful about running the lithion batts down too much. An article that will tell you everything you might want to know about camcorder batteries (and more... think it's 50+ pages) is available at the anton bauer site. Go here (http://www.antonbauer.com/Downloads) and then click on the "handbooks" link. This might be helpful for your project.

By the way is 200ma the recommended current or is that the max rated or is that the typo (I haven't used the super bright LEDs but this seems like a high current in general for a LED)?

[zakart]

Can you share the source with us? I am experimenting with an LED version of an outside lamp (the kind they use for architectural lighting). It has around the same number of LEDs, but cost several times what you are telling us about.

so the LED panel i bought from ebay for $60 for two of them and if you look around u can find them cheaper

[zakart]

I also bought two TVMP adapters, and two pieces of 3/16" steel so that i can put the lights on a stand. So far i spent a little over $100.

heres a link for the TVMP adapter

I got the steel from home depot for $13. Im still trying to figure out how to connect the panels to the steel so that i can tilt the light up and down.

[zakart]

I just got the lights today and they are really nice. the light is soft and beautiful. ill post up a pic when i put them together all the way.

[Pat Hughes]

Hi Richard, I really cannot promote or sell my custom design here but I have actively been improving on my LED design since my last reply. I am awaiting for the newer, brighter, more efficient neutral white LEDs to replace the ones that are in the picture. They will be able to run from anywhere from 6.5 to 18 volts DC. I expect them to be available before the end of January 2010. All I can say for now is that an array of 12 leds will be used and underdriven by 50% to achieve a maximum lux rating os 2500 at 3 feet away. The horizontal beam spread will be over 110 degrees with no fallout at the edges.That will cover nicely a full zoom-out of a typical HD 16:9 camcorder with room to spare. With the newer leds, the power consumption from the battery will be LESS than 25 watts and each led will consume about 500ma at 3.08 volts (1.54W). Each led will output slightly more than 200 lumens. The newer leds can handle easily well over 1000ma each but the needed efficiency for my design as well as attention to heat output makes the 500ma a sweet spot driving range for the design.In answer to your question, a Sony NPF-970 series battery is more than adequate to drive the present lamp but with the new leds, that same battery will have a run time approaching 2 hours at full brightness. That is a dimmer and the front is unbreakable Lexan. The overall dimension is the same as well as the weight (3 X 3 X 2.5 inches) 17oz without batt. This design took me well over 9 months with extensive testing. Particular attention was given to the reliability, performance and output. The Color rendition is 4500K . I am prohibited to sell these units here for now but in the near future, I will apply for licensing and adverising rights.

[Norman99]

Pat, that has got to be exactly what I have been looking for. That light is perfect for my needs. Are those leds in there the famous Cree MCE's ? if so you really know your stuff. I hope the output is over 2000 lumens. Where can I try and buy one? Thanks

[Pat Hughes]

Yes, those are the MCE's at the highest bin values. They can output well over 650 lumens each for a total of 2600 lumens. However in order to run at max efficiency and minimal heat, I had to underdrive them by a factor of 70 percent of rated max. The newer XPG's at the S2 bins are not out yet in neutral whites but when they are commercially available, a total of 12 will be installed in the light for a total underrated lux value of 3200 lumens. A slightly larger unit will house 18 of them with integral silent fan and a speciall copper grid heat sink to output more than 4500 lumens at 3 ft. making it the brightest led on camera light on the planet. Sorry, can't sell them here but I will post pictures soon.

[CiPO]

Hi

where can I find some battery plates (to be used on my own DIY prj) for e.g. the SONY batteries ?

[Richard Crowley]

Hi

where can I find some battery plates (to be used on my own DIY prj) for e.g. the SONY batteries ?

I just got a nice Marshall LCD monitor. It has 6-8 different battery plates available for different brands/models. I would try contacting Marshall to see if they will sell you a "replacement" battery plate.