HOWTO detect hidden video cameras

Instructables has just posted its latest installment in its collection of HOWTOs inspired by my new novel Little Brother, a young adult book about hacker kids who use technology to win back their civil liberties from the Department of Homeland Security.

This week, it's instructions for building a simple device that will let you spot hidden "pinhole" video cameras:

With one hand, hold up the toilet paper tube to your eye. With your other hand, hold up the flashlight at about eye level and point it away from you. With one eye, look through the tube and scan the room. If there are any small points of light bouncing back, inspect it further. It might be a camera.
Link, Link to feed of Little Brother Instructables


  1. Corey, I didn’t know you had a new book called Little Brother. You should post about it more often…

  2. OT but might be useful if spiders are spying on you.

    This technique, minus the arguably superfluous tube, is great for finding roaming spiders at night or in a dark room. Their eyes shine back like colored jewels.

  3. #2 Ok, I was going to build one of these, but now you’ve just creeped me out. Spiders scare me to no end.

  4. And how are you supposed to hide the fact that you are looking for a cam when you have a toilet paper roll stuck in front of your eye, flashing a light around ?
    Interesting stuff nonetheless !

  5. @Albedo,
    That’s how they find alligators too. I lived in an apartment complex with TONS of alligators in an adjoining lake. I saw game wardens doing that at night sometimes, sans cardboard tube.

  6. This is a useful post, us living in a post-1984 styled society where we’re being watched for our own “safety.”

  7. In my family toilet paper (and paper towel) tubes have always gone by the name “doot-de-doot”. Just thought you needed to know.

  8. Of course, the alternative is to get your death god to suss them all out for you by bribing him with the promise of apples.

    /obscure anime reference

  9. Heh, maybe I’m just too much of a nerd, but that’s not that obscure of a reference Misshallelujah. It’s actually one of the first things I thought when I read that part in Little Brother and this post.

  10. It was exactly the first thing that crossed my mind when I read it.

    But I am that much of a nerd.

  11. I’ve rarely known anyone who knew about the spider-finding power of flashlights before. Long ago a friend told me and I told some friends and we’d get together to walk around at night spiderhunting by holding flashlights to our foreheads. If you walk around like that and look into the center of the beam you can always find spiders. It’s very creepy, because you’d see this little glowing spot in the weeds by the house, and then you’d move in on it very slowly, staring into the light, and you’d get to where all you could see was this growing orb of light, fluctuating on the weeds with this little spark in the middle that would get larger and larger as you approached until AAARGH there was a huge spider looking back at you. We were usually pretty buzzed when we did this.

  12. I’ll have to try the flashlight-spider thing. Finding scorpions with UV lights (blacklight) is great fun, however. Their bodies fluoresce quite dramatically under UV. And then you never walk barefoot again.

    For human camera detection, I prefer the mask approach. Or the social-engineering method: “I understand you’ve been having some problems with your CCTV, could you point out the cameras?”

  13. Used this to find wolf spiders, known hunters to do this to poach deer, remember some school chums using this for ‘rabbit golf’, and I’m trying to remember the name of the guy who proposed this technique for searching out extraterrestrial life.

  14. @13 — beat me to it. Or worse yet, when you look up in a tree and see them there, waiting to jump down on you. Or fall off and reflexively sting you. Whatever it is they do. Friend of mine had that happen while walking to her mailbox. ouch.

  15. Bah, this instructable forgets the step where you tape a playing card to your forehead.

  16. This reminds me of the technique mentioned in Stephenson’s Diamond Age for detecting ‘mite’ activity. (Since the nanobots in that novel were omnipresent and communicated via visible light, you could get an idea of how much activity is going on by making a closed-off tube out of your hands and watching for flashes in the space enclosed.)

  17. @#1
    Your Sarcasm is awesome.

    I just can’t wait until the Steampunk version of this comes out!

  18. #1 and #21……

    If we could figure out a way to have the spiders naked and having sex we could bring Xeni along for the ride and have a perfecta!

    Now, how could we acheeve (#3) a trifecta?

  19. regarding #8, in “a child’s garden of grass”, they used the similar term, ‘der-der’.

  20. And in case you don’t care to hold a flashlight to your forehead, a Petzel headlamp works well too. I learned this as a frog-finding trick from a guide in the Amazon.

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