I never knew this...

[KennyR]

...that webcams can see the IR LED on remote controls light up. Try it yourself - here it shows a whitish-purple. I can even see the LED lighting up nearby objects. It's totally invisible to the naked eye.

So...if I had an IR flashlight, I'd be able to 'see' in the dark with a normal webcam? Surely not...

[iamaboringperson]

KennyR wrote:
...that webcams can see the IR LED on remote controls light up. Try it yourself - here it shows a whitish-purple. I can even see the LED lighting up nearby objects. It's totally invisible to the naked eye.

So...if I had an IR flashlight, I'd be able to 'see' in the dark with a normal webcam? Surely not...

Yes, you can see in the dark.

I learned about 10 years ago that VHS (etc. etc.) camera's will do that, also.

Some CCD cameras come with a bunch of IR LED's attatched for night viewing.

[FluffyMcDeath]

KennyR wrote:
...that webcams can see the IR LED on remote controls light up. Try it yourself - here it shows a whitish-purple. I can even see the LED lighting up nearby objects. It's totally invisible to the naked eye.

So...if I had an IR flashlight, I'd be able to 'see' in the dark with a normal webcam? Surely not...

Video cameras going way back can do that. The CMOS sensors are particularly acute in ir. I've often used the ol' video camera to check if the batteries in the remote are dead!

And indeed, if you had a bright enough IR source, you would be able to shoot in the dark and no-one would be aware how illuminated they are. CMOS detectors are so sensitive to IR, I believe that they usually have some kind of IR filter installed.

[that_punk_guy]

This is something I've wanted to experiment with for a long time. You can pick up a lot of IR with a standard digital camera too. (I also had an ex-bank security camera that was extremely sensitive to IR and gave a brilliant picture even in very low light conditions.)

When I enquired at the electronics shop a few months ago the guy behind the counter suggested that the cost would be prohibitive if I wanted to flood a room with infra red light. May have a nosy on the web.

[blobrana]

Hum,
Better remember to remove the inbuilt IR filter that they put in front of the lens...
(which means disassembly of the camera - an easy job, i`ve done it myself)...

And there are (the opposite kind) Ir filters that you can fit that will just let through IR light so you can take weird photos during the day...

BTW, black and white is best

And it would be a nice if you could post a photo of a A1200 mobo glowing in the dark...

[Karlos]

that_punk_guy wrote:

When I enquired at the electronics shop a few months ago the guy behind the counter suggested that the cost would be prohibitive if I wanted to flood a room with infra red light. May have a nosy on the web.

How about making a grid array of super bright IR LED's - the kind you can pick up for a few pence a piece. I'm sure you can illuminate a decent area with those. I have some ordinary super bright red led's (years old now) that are 5000mCd brightness - a few together is like a torch beam. A decent grid of IR ones of a similar output would be like an IR floodlight :-D

[Vincent]

that_punk_guy wrote:
(I also had an ex-bank security camera that was extremely sensitive to IR and gave a brilliant picture even in very low light conditions.)

Ah, now the truth comes out about tpg's shady past! :-P

Not that brainy tho, most people steal the money in the bank, not the security cameras :-P

[Karlos]

@Vincent,

He was coming back for the money but by then they'd seen his face, getaway car...

[that_punk_guy]

Are you suggesting, sirs, that I am some kind of cwiminal? The nerve! :roll:

:lol:

[Vincent]

that_punk_guy wrote:
Are you suggesting, sirs, that I am some kind of cwiminal? The nerve! :roll:

Well, here'th the thing....

You thtole the thecurity camera, but you forgot to get the tapeth from the theetheectv room :-P

[that_punk_guy]

 :-P

[Dan]

I wonder how one of those heatlamps, used for piglets and chickens would work as an source of IR-light?
200 or 300W it would light a bigger area than a diode
but then again they give of visible (red) light also

[that_punk_guy]

Dan wrote:
I wonder how one of those heatlamps, used for piglets and chickens would work as an source of IR-light?
200 or 300W it would light a bigger area than a diode
but then again they give of visible (red) light also

You could install them behind filters, in fact I think it's been done (going by what the guy at Emery's told me) but it sounds awfully inefficient.

[Karlos]

'lo

that_punk_guy wrote:

Dan wrote:
I wonder how one of those heatlamps, used for piglets and chickens would work as an source of IR-light?
200 or 300W it would light a bigger area than a diode
but then again they give of visible (red) light also

You could install them behind filters, in fact I think it's been done (going by what the guy at Emery's told me) but it sounds awfully inefficient.

There's IR and there's IR. Thermal radiation is typically a longer wavelength than that used in IR applications. The latter is really not far beyond the visible spectrum - 650nm or so IIRC (aka near IR).

I don't think the CCD's in normal cameras etc are receptive to "thermal" IR. Unless your webcam sees a hot cup of coffee as a light source, that is ;-)

[that_punk_guy]

He he ;-)

Well, either I'm mixing up my light sources or Mr. Emery was bulls***ting me. I did think of using an awway of LEDs, though. Something for when I have a little more surplus cash, I think. :-)