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Infrared Webcam HOWTO
Geoff Johnson writes "Some of the Slashdot readers may be interested in this page I put together. It describes how to make an ordinary webcam see in the near infrared waveband."
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Infared web cam? Somehow I don't think Bubble Cam would be quite the same at night. :D
I do wonder what the most common applications for Linux/IrDA are, considering the trend I've observed where among the most commonly requested Linux HOWTOs recently have been 'laptop', 'infrared' and 'webcam'. Is everyone building infrared webcams?
I Want To Believe
...and, soon to come, the THEMcam!
SCNR... sometimes I'm amazed at what kinds of typos make it through to the frontpage.
But besides that, very nice article. I personally found IR very useful for some surveillance-type situations. A few years ago, my father set up an IR-sensitive camera and an IR diode in a birdhouse in our garden, which allowed us to watch the new-born ones without creating any disturbance.
Does anybody think that coupled with a pure IR source of light this item would be useful in catching would-be prowlers without alerting them? OK, probably a stupid idea...
GreyPoopon
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Why is it I can write insightful comments but can't come up with a clever signature?
WTF is the timelapse movie doing there?
That's the guy thinking "before f*cking up my webcam to remove the IR lens, I'll do something normal with it so I won't feel so bad when it ends up dead on my table". His hack worked, so he posts both...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Hmm, I opened my sweex webcam (the same he has) and unscrewed the lens. But my IR filter is round (so not a square as in his webcam) and won't come out.
Lets hack some cams, stick them on $89 lcd handheld tvs and send them to tibet as freedom fighter nightvision goggles.
It might make the fight more interesting.
altho, most that ive seen ahve the IR filter directly attached to the CCD.
:)
you would remove the CCD, then remove the 'piece of glass' from it.
some cameras achieve this effect differently, I have not quite worked out how they work.
For example, Sony camcorders that have 'nightshot'
also have an IR filter, but I suspect its something different. the switch not only engages some IR illuminators, but does something in the lens block itself. (switches something in/out mechanically)
I know that the IR filter at the CCD remains there, its in a fixed position.
I am now curious and have to dissasemble a sony lens block to see
I used to work on cameras, and I have removed the IR filters on cameras before for a bit of fun.
if you can get enough IR leds going you can get it pretty well lit.
Altho, the resolution is probably not going to be that great at a distance.
Cadillac has an interesting thermal system, I haven't really dug into it in depth, but basicaly the sensor is a bunch of capacitors similar to a ccd sensor. When the IR image is focased on the sensor, the heat causes the diaelectric between the capacitor plates to warm up and expand changing the charge on the capacitor and make it readable.
Sooner or later someone is going to hack the system for some serious geek factor. I could see someone hackering several of these different systems together for some cool false-color IR video. I used to do quite a bit of IR photography used Kodak's IR false-color slide film, green showed up as blue, red was green and IR was red if memory serves me correctly. The biggest problem was the film used the old-fassioned E4 process, so you either had to send it to Kodak or do it your self
Apocalypse Cancelled, Sorry, No Ticket Refunds
I have a camcorder (analog, large by modern standards) which has a mode in which it takes infrared images. It has a bright infrared LED on the front, so it can work as an active infrared system in total darkness (it gives weird green-and-white images). The thing is, when it is in normal daylight mode it can still see IR, and you can see, as you say, remote controls as flashing lights. Which makes it's own remote control look silly when we use it to start/stop recording.
# cat
Damn, my RAM is full of llamas.
Actualy this is pretty much WW-II style technology, the old Sniper-Scopes used active IR like this web-cam mod. Now the problem is passive IR is so common firing up an IR illuminator is like painting a bull's-eye on your forehead. It's so common, we put blue filter on our flashlights to block the near-IR and IR output; visible light is less damgerous the IR at night!
Apocalypse Cancelled, Sorry, No Ticket Refunds
Will this capture the right range of infra red to detect heat? If so, then I could see using it with a laptop on a cold day to see where I need to improve the insulation on my house.
...Get one here: http://www.mair-family.org/Downloads/ Geoff says the software he had isn't very good. I couldn't find anything I was prepared to pay for so I wrote my own and publish it at that link. Sorry Windows only and WMV output. You can read the feature list for yourself but, in terms of Geoff's difficulty, it will capture frames at between 4s and one hour per-frame (configurable) and create a 15fps WMV.
Go ahead, /. my web server...Hopefully my ISP is tolerant.
I usually prefer to use a high intensity Xenon light with a filter on the front. Xenon has a nice spike in intensity at about 700nM and makes an awesome covert searchlight.
It's "It's" not "Its"! :)
toresbe
Five minutes after I read this I dug out my old IBM PC webcam and started tearing it apart. Five minutes later I had a working IR webcam. Now I want an IR flashlight.
Took the whole camera apart, removed the optical pass filter from the CMOS chip, replaced it with an IR-PASS filter (rejects lessthan 750nm)... and I have a visible focus / IR sensitive camera.
Great shots, too
1st test shot here: http://www.deviantart.com/deviation/12473546/