Cheap led light solution for on board camera (5usd)

capt chuck said:
That's absolutely correct. For the pupose of this device the easiest method would be the way the 9.99 version works. Since there are a number of LED's instead of trying to dim each one individually, dim the entire assembly by switching off a few of the LED's entirely.

An alternate solution to this and to the ones offered in the links (if you really want all the LED's to light) is to switch the current on and off very quickly (several thousand times a second). The more time the current is switched on in a second the brighter the LED will glow. There are integrated circuits that are well suited for creating this kind of switching current (a 555 timer chip is very commonly used).

Provided it works as advertised, however, it would be hard to beat the 9.99 version where someone has already done all the work for you.
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Right, that's what some of those circuits were doing. Well I guess as long as it's a high enough refresh rate you won't notice a flicker but that sounds like the biggest potential problem with an electronic dimming solution.
 
I got one of these a WHILE ago (like October last year). unfortunately the LEDs are blue so everything looks less than stellar. I'm planning on replacing the LEDs with pure white ones, cutting the box up and making it into a ring light. when I have time that is... which won't be any time soon :o]
 
Cool Lights said:
to find a ring about 6" in diameter, get a plastic speedring of the same diameter with the rubber tipped thumbscrews and voila: you've got a ring light that attaches, in a "professional way" to just about anything including a lens of practically any size.
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First question: is there such a ring?

Second question: how to do the pcb ring to hold all the LEDs.
 
Cool Lights said:
As I understand it, dimming with LEDs is more complex than it would seem as LEDs are current based and require a constant current source. This really means that you need a special power supply to do it right. They call these modules "LED drivers". Before I thought it was just an excuse to overcharge for a power supply but now I realize these things really do have a good function. I'm still in learning mode on all this though. Here's a pretty good article on the subject for anyone that's interested:

http://www.mikesflightdeck.com/led_dimmer.htm
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Yes, that article is quite good, particularly if you look at the last circuit using the 7805 regulator. But the author mentions that the regulator may get a bit "toasty", which I think it's due to they using 12v as the main supply. You are wasting energy on this regulation and it goes away in heat.

Some time ago, about two years or so, there was an article here in DVXUser with a LED light project that was based on 7.2v video batteries. So you can use the same batteries you use on your camera. Unfortunately it was taken out and I don't know why. That would be more effective.
 
morten said:
I got one of these a WHILE ago (like October last year). unfortunately the LEDs are blue so everything looks less than stellar. I'm planning on replacing the LEDs with pure white ones, cutting the box up and making it into a ring light. when I have time that is... which won't be any time soon :o]
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Morten, I was looking at the color of the LEDs - and agree they're too blue as is. To keep with the low cost (and time) approach, I'm going to do some quick tests with a few Rosco cc gels; find out which one makes the tone most neutral; then affix it to the front of the light. Hopefully the gel that works best won't significantly reduce the light output.
 
Carlos,

Yes, a ring like that exists, I just have to find the source. I had a softbox I got from Ebay a couple of years ago with a 6" plastic speed ring. Wouldn't have been good for hot lights but it would sure work well for a ring light. As for the LED rings, we'll see about that later. Too many projects going right now.
 
I came across a different LED light that looks 'promising' unless you really need a ring light (I don't):
http://www.dealextreme.com/details.dx/sku.485

$12.80 shipped gets you a 68LED light. I've ordered from dealextreme once before. The build quality of the lights I got is not so great, then again I don't expect much at those prices. Here's what looks like the same light for $20:
http://www.ledshoppe.com/Product/ledp/LP1033.htm

Unlike the UFO, it has a rim in front of the LEDS so you can gel it easier, maybe even add a diffusion gel. I would cut the barrell off just behind the switch and use an external battery pack. I'm thinking of getting 2 of those, just wanted to hear other people's opinions.
 
That looks interesting if you cut the back off. Now just add a hotshoe adapter and you've really got something.
 
Could anyone do a comparison between these lights and other on camera lights, specifically the 20/40 watt or 50/100 watt bescor lights?
 
There is no comparison. These are camping lights. They are nearly completely unsuited to the purpose of using it as a camera light, except for one factor: they do produce light, at a dirt cheap price.

Basically any properly-engineered on-camera light is going to do a better job than these. These are lights designed to hang up in your tent to read at night when you're camping. Can they be pressed into service for video use? Yeah, just like workllights can be pressed into service to work for set lighting, but just like worklights they're not very good at it; they just happen to be cheap.
 
>but just like worklights they're not very good at it; they just happen to be cheap.

Well said.
 
I have one of these rechargeable desk lamps with cheap LEDs in it--really blue. Seems like you could ruin your eyes if you used it often enough to read by. I certainly wouldn't want to try to use it for video.
 
Cool Lights said:
I have one of these rechargeable desk lamps with cheap LEDs in it--really blue. Seems like you could ruin your eyes if you used it often enough to read by. I certainly wouldn't want to try to use it for video.
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Try to gel it with 1/4 CTO, you'll see a big difference.
 
I was playing around with mine the other day and once its color balanced to it it looks fine as long as its the main source of light, so it would work for ENG stuff but i dont think it would work to good mixed with real lights.

Im gona have to try geling it when i get home tonight and see what happens.

I will definatly just keep it in my camera bag since its so light, and could come in handy if i dont have my real on camera light with me.

One problem though is i need to figure out a way to mount it to my camera since i shoot with my dead cat on my shotgun most the time.
 
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