IR "floodlight" using LEDs?

They are the same as the uncolored ones. These are rather ordinary incandescents with the filament operated at a higher temperature than usual. The blue coloring removes some of the red and yellow light ans a small amount of the green light to make the color more like that of sunlight. Without the blue coloring, the nominal color temperature is

I would advise against staring into these, but I don't expect instant eye damage from very briefly looking directly at one - at least any of the frosted ones, and my experience so far is that these are normally frosted. In any case, tungsten at 3400 Kelvin is not as bad to look at as the Sun is...

Then there are the short life halogen movie and video lamps and projection lamps... Those usually have color temp. around 3300-3400 K and are usually clear rather than frosted. I have looked at these enough times (never for long) and I don't think I have any eye damage from these yet, but I would advise against staring into them or looking directly at filaments that hot for more than a fraction of a second. I have a rough calculation that a couple seconds of staring at these is safe (assuming one's pupils constrict), but then staring into a 1 milliwatt laser for 1 second is supposedly safe (barely) - something I would advise against doing.

- Don Klipstein ( snipped-for-privacy@misty.com)

More FYI. The commercially available IR illuminators I've seen cost in the area of $1 for every IRED they contain. I can build them for about half that using an LM317 in the current regulating mode and surplus

It won't work. I have tried. The unfocused/unreflected LED's will only illuminate out to about 15-20 feet, if you are using a gen-1 NV tube viewer, and a CCD-camera is about equal to that at best. You can put one IR LED into a flashlight-base and put it in a flashlight (with a dropping resistor) and get a -fairly- good small beam out to 40-50 feet or so, but the flashlight you use MUST have a sweep focus, that can adjust from spotlight to flood. Because the "flood" setting doesn't illuminate very far, but the "spot" setting is too bright to be of much use up close. ....THere are companies that sell IR-LED heads that they say are for this. I have not tried any of them, but from my own attempts (with a 19-LED unreflected unit, as well as a couple single-LED reflected attempts) in a Mag-light body I would say it doesn't work.

----- The best way to make a IR light source for a gen-1 or CCD camera is also the easiest way: use a regular flashlight, regular bulb and get a deep-IR glass photographic filter. These filters will not allow any visible light through at all, but they are expensive: the Hoya-RM90 is one. A much cheaper way is to put a deep-red and deep-blue filter over a regular flashlight. This is visible-red if you are looking right into it, but the light it casts is not visible--yet shows brightly in gen-1 NV scopes. CCD cameras catch it well too, if they have no IR filter. As to how well the animals can see this, I don't know. My experience was that wildlife were far more concerned about noises than a red light, but you may be after different animals.

----- If you really want to see in the dark [WITHOUT using active lighting] the -only- way is to get a gen-2 or gen-3 night-vision scope, one that adapts onto your camera of course. Figure $1200+ US for a gen-2, $1800+ US for a gen-3. This will allow you to film in any lighting circumstances outdoors, probably without any additional lighting at all.

----- As a sidenote, I also have tried stacking two gen-1 scopes. By taking the eyepiece off one, and holding that up right in front of the other. It doesn't really accomplish much; the image is somewhat brighter but far less clear--the "background noise" brightens more than the image. You need to use an f-stop on the scopes to see anything at all--I used pieces of kraft paper over both lenses, with small holes cut centered in them about 10mm across--or else the rearmost image turns up too bright. Two cascaded $100 gen-1's won't equal a single $1000 gen-2. Gen-1 NV tubes use electron inverters internally, that drastically ruin/blur the images they produce. A gen-2 or gen-3 NV scope image is far more clear than a gen-1 is, and amplifies light higher and with less noise as well. ~~~~~~~~

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Thanks for all the good info below. I think I would get one of those

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but

$1800+

all.

in

bright.

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well.

Just watch for the heat produced by such a beast.

Well, isn't that kinda the point? They are looking for IR, after all. :-)

Cheers! Rich