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MPVRr Feb 10, 2006 10:04 AM

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I just picked up one of these at Circuit City for $4.49. It's actually a bicycle tail light, so it has red LEDs, but it looks like it can be modded with white LEDs fairly easily. I can also see how a 1/4x20 screw could be attached to mount it on the cams tripod mount.

I'm not very knowledgeable about LEDs though. Does anyone have input about a good (cheap) type of LED for this application (maybe even an IR LED for night use)?

Thanks in advance,

MPVRr Feb 10, 2006 10:38 AM

Hmmm.... It looks like the LEDs may be available cheaply from :

Looking for suggestions.... 3mm or 5mm... warm white, blue/green :??

Thanks in advance,

Tek465m Feb 10, 2006 12:45 PM

Some of my favorite places for supplies, (my wife calls it junk):

LED Section

LED Flash lights

IR LED Illuminator kit

I was also thinking while looking on the Ramsey site. Another option if you wanted to take night video, since the MPVR has a video in you could always use an external CCD Lipstick cam. Or even a wireless "nanny cam".

I originally got the MPVR to record wireless video from RC planes, Model rockets, and such, without having to drag a lot of equipment around. The Hybrids really lend themselves to the creative mind.

MPVRr Feb 10, 2006 1:06 PM

Wow! That place really is a geeks goldmine.

Thanks for the links!

Tek465m Feb 10, 2006 1:18 PM

" I'm not very knowledgeable about LEDs though."

The thing about LED's is that they are current controlled devices. If you don't limit it with a resistor, you'll get a nice flash before it burns itself out. Rule of thumb is 20mA.

The other problem you might run into is the voltage needed for the LED to start conducting. Red LED's are usually the lowest at around a volt. White and blue LED's are around 4 volts. An DVM (Voltmeter) with a diode check will tell you the voltage needed.

That bicycle light might not have enough voltage to turn on another color LED.

MPVRr Feb 10, 2006 1:49 PM

Good call. Thanks again!

I wonder if I can reduce the number of LED's proportionately, and just jumper across the ones that I exclude. There are six on the board now, with 2x AA batteries.

I'll have to do some more research. At least, if I get a brilliant flash and a burning smell, it won't have cost much. :G:G

I'll remember to wear goggles for the initial test.


fishycomics Feb 10, 2006 1:57 PM

MpVr. can you test this just one more State over, so I do not get an aftermath?

I have a 9 led white flash light and well ummm rather leave it alone Lol 3x aaa system as long as the batteries are seriesforvoltage the more the higher and parallel the more the max same voltage. hope that helped a lil.

MPVRr Feb 10, 2006 2:04 PM


Too late Fishy..... sorry.... :O

fishycomics Feb 10, 2006 2:35 PM

that's alright i am gonna get the white ashes in a few days...............

the flashlight can be used but may not be strong enough at all, it may just rab the persons face and part body. 3 feet may be enough.

a stronger light like aflourecent may work wel, they make a small one throwsa different light. but no maximum distance.

what i found great was a reflector with a bulb. what I find not good is an over head incadecent light

he badpart about lighting is if you shine foward only the front will have light and anything behind will not

what is the purpose of the condition that you need to film for? just general stuff?

I do want a better lighted camera as well and the jvc and cannon camcorders use 2 led lights we need to find out those leds and utilize them to our cameras.

MPVRr Feb 10, 2006 3:16 PM

I really just want a general light for low light conditions. I figure that I can play with the LED positions to get a nice dispersal, and heck, it's just fun to tinker. In the end, I hope to have the equivalent of a CameraBright, but for 75% less (and have had some fun doing it).

Also, now that I know that the MPVR likes IR, I hope to make a cheapo night light for my MPVR. I may never use it for anything particularly productive, but it would be fun just to do it...

You know...?


fishycomics Feb 10, 2006 3:18 PM

keep some tabs and instructions on it go to freewebs and sign up and do an instructional video and pic ther.

MPVRr Feb 10, 2006 3:26 PM

Will do!

MPVRr Feb 11, 2006 3:19 PM

Well...the IR thing is a bust. 4 IR LEDs do nothing to illuminate a dark area. I'll be experimenting with white LEDs next.

fishycomics Feb 11, 2006 4:11 PM

got a whole bunch here I tried four I tried 8 in a flash light I just stuck to a reflector light lol

here is a 40 watt reflector I hada 60 watt incadecent up here some where lol

see it is dark atfirst but when I moved in and light is just behind got lighter I bet if I move in front of the camera it will light up

juandelacruz Feb 13, 2006 7:26 AM

Color cameras are deliberately insensitive to IR. manufactures put IR filter in the lens because IR will interfere with color. true night vision cameras are the black & white ones. Other cameras equipped with night mode (like my sharp video CAM) have a mechanical lever todisengage the IR filter and the IR illuminator ( high power IR leds) will be turned on. Its quite neat because you will be able to see in complete darkness up to th power of the IR illuminator.

If you want to make your DV6800 IR sensitive, you have to remove the filter but will make the color system useless.

About LEDS:

Blue, psedo white and white LED's are different from ordinary Yell, Red or Green LED. The rating of the blue and white is approximately 4.0 volts at 30 mA while the old LED's (red, green, yellow ) is about 1.7 to 2.2 volts at 20 mA.

You can conect in series and parallel to obtain the seried voltage but if the supply is higher that the LED voltage, you better use a resistor, examples:

3- white LED if connected in series (watch out for the polarity) can be connected to 12 volts max.

If connected in parallel can beconnected to 4.0 volts max. If you want to connect to 6 volts then you need resistor, computation as follows :

assume 30 mA each, 3 diodes will draw 3x30 = 90 mA

Voltage to be dropped by resistor = 6volts - 4 volts = 2 volts

Required resistance (by ohm's law): 2volts divide by0.09 amps or 90mA= 22 ohms

Youre in luck because 22 is a standard value, other standard values are 18 and 27 ohms.

For power rating , again by ohm's law: 90mA Squared X 22 ohms = 0.178 watt, the closest value is 1/4 watt.

Summary, for 3 white LEDs to be connected to 6 Volts source, you have to connect 22 ohm, 1/4 watt resistor inseries.

Of course you can always connect the LED directly to the 6 volts source, depending on the power of the battery I do not know how long (sec or min) the LED will lasts.

I hope I did not bore the readers ;)

MPVRr Feb 13, 2006 11:32 AM

Whew! This is good stuff. Thanks!

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