6 comments

  • kragen46 minutes ago
    People normally do this by scanning a 10mW 832nm laser with a mirror, according to Dan Gelbart in <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=0MtRxX0crjU" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=0MtRxX0crjU</a>. The lecture is 77 minutes, covering nonlinear junction detectors, digital calipers, the US-embassy bug in Russia, laser microphones bounced off windows, and geometric errors from material relaxation. The bit about camera detectors is close to the end. Works for eyeballs too.<p>Lensless sensors (for example, using compressed sensing, or Hadamard shadow masks) can presumably defeat this, but also, watching from far enough away should defeat it. Hard to do that inside a pervert&#x27;s AirBNB, though.
    • mitthrowaway222 minutes ago
      The junction detector is a truly brilliant idea that, unfortunately, is probably rendered nearly useless now that everything in the world has embedded electronics in it.
  • carlostkd3 hours ago
    Until someone develops hidden cameras with AI that will be auto turned on couple of hours later after detecting presence at that time a scan was already performed and nothing was found.....
    • zack68491 hour ago
      this works by looking at the physical characteristics of the lens, so on or off should work regardless, you could have something with some kind of internal shutter to cover the lens maybe
  • fidotron6 hours ago
    If this worked with IR, and so non visible, it might be even more useful.<p>Great idea though.
    • RyJones3 minutes ago
      Walk around your neighborhood and see who has security cameras.<p>Security camera through PVS14 <a href="https:&#x2F;&#x2F;youtu.be&#x2F;gEWniEhtE2k" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;gEWniEhtE2k</a>
    • baking5 hours ago
      But then you would need an IR camera instead of using the phone&#x27;s camera. An IR camera should be able to find some hidden cameras passively by detecting a heat source.
      • hammock5 hours ago
        Can’t phone cameras pick up IR?
        • superxpro124 hours ago
          the raw sensor can, but there&#x27;s usually an IR blocking filter in the lens assembly.
          • TheRealPomax4 hours ago
            not really, no. It&#x27;ll happily show you IR (just point it at your remote control with the camera active, and press some buttons. Enjoy the light show on your screen that your eyes don&#x27;t see).
            • ChrisMarshallNY3 hours ago
              Yes and no. The IR filter is pretty strong. If you have an intense IR source, then it overwhelms the filter, but it would blow out the sensor, without it. The sensor is biased towards IR.<p>I&#x27;ve converted cameras (DSLRs) to IR, and you use a replacement IR-pass filter. The IR-blocking (default) filter looks like a piece of blue glass. The IR-pass filter looks like a piece of black glass.<p><i>NOTE: It&#x27;s not perfect. The DSLR image processors and calibration systems are calibrated to the IR-blocking filter. Stuff doesn&#x27;t work the same, once you convert.</i>
              • spiorf3 hours ago
                I did that with a cheap webcam years ago. All my black hoodies were white, and so were the leaves on trees.
                • ChrisMarshallNY3 hours ago
                  Yup. IR images are cool. Snowscapes in the summer.<p>Cheap cameras are best, as they don&#x27;t have too much precalibrated stuff.<p>I converted a Nikon D70s, and it still works great.
        • HnUser124 hours ago
          I’d think so. My iPhone can see my remote’s IR.
          • ssl-34 hours ago
            It sees it poorly. IR is deliberately (though imperfectly) filtered in the optical path.<p>The dim purpleish glow from a remote that is seen through [many] digital cameras would be quite bright if this IR filter weren&#x27;t in place.<p>It doesn&#x27;t have to be that way, but it usually is that way anyway -- as a design intent.<p>Cameras used for surveillance, meanwhile, often lack these filters. They&#x27;re designed with more of a focus on getting any kind of image at all, including when working with infrared illuminators in the absence of visible light. Some even have mechanical elements that move filters out of the optical path for night mode.<p>This differs tremendously in comparison to a camera that is designed to produce very beautiful visible-light photographs.<p>(This all conspires to mean that IR is kind of a non-starter for this sort of cell phone camera hack.)
            • HnUser121 hour ago
              Ah ok that makes sense. I just pointed at my remote and it is very very dim.
          • happyopossum4 hours ago
            That was true years ago, but I haven&#x27;t been able to use an iPhone camera to pick up an IR signal in a long time. Just tested it to be sure they hadn&#x27;t reverted to an unfiltered lens (17 pro) and nope, no IR visible.
            • HnUser121 hour ago
              I pointed at the remote of my fan and I can see it. I am on 15 Pro. However, as the sibling comment said, it is very faint so I&#x27;d guess not very realistic.
            • ThePowerOfFuet3 hours ago
              Try the selfie (aka front-facing) camera; often they are not equipped with an IR filter.
        • lightedman5 hours ago
          Depends on how cheap you go - most of the cheap ones that take images where the blacks look grey likely do not have an IR filter on them. Most quality phones will use a camera with IR filters on them - blacks look like blacks.
    • askvictor3 hours ago
      Pining for the days when phones had IR blasters (e.g. galaxy s6); that would work perfectly for this
      • molybd3num3 hours ago
        some more modern phones from xiaomi still have IR blasters
    • IshKebab5 hours ago
      Why would that be more useful?
      • evilduck5 hours ago
        Perhaps to avoid tipping off the entity recording you by blasting their hidden cameras with bright lights. Granted, the PoC device in the article is not exactly subtly looking, but if you could turn it into a sleek device it would be more useful. Not playing your hand while you&#x27;re under surveillance lets you control the information they&#x27;re receiving.<p>Though the bigger issue with my theory is that while most cell phone and webcam devices have IR filters, many surveillance cameras intentionally do not.
        • dylan6044 hours ago
          If you&#x27;re being surveilled in a way that you don&#x27;t want to tip the observers is one thing, but if you&#x27;re in an AirBnB type place, fuck &#x27;em. I&#x27;d even be fine with running some lasers in the place that ruins the sensor.
          • expedition324 hours ago
            I&#x27;m an adult male so I don&#x27;t care if someone wants to record my dong but this is very helpful for families with kids.
        • rgj5 hours ago
          Unless the hidden camera has IR capabilities.
          • evilduck3 hours ago
            That&#x27;s actually much easier to detect, any camera without an IR filter would show an LED emitting where your eyes did not, no complicated solution necessary.
  • brunoborges6 hours ago
    I wonder if it works with smart glasses.
    • thesuitonym5 hours ago
      You don&#x27;t need this to detect smart glasses, they&#x27;re very obvious.
      • stronglikedan4 hours ago
        For now, but there&#x27;s really no point in detecting them anyway, since there are plenty of truly concealed options for those that really want to be pervs.
        • dbspin3 hours ago
          Strongly disagree. Most crimes are crimes of opportunity. Most &#x27;pervs&#x27; don&#x27;t start out that way either. Detecting increasingly easy to conceal sousveillance devices is probably essential for any kind of normative public sphere to continue to exist.
      • doodlebugging5 hours ago
        Proctologists agree on this one thing that smart glasses can never conceal.
  • Cool, but we need that for microphones.
    • poly2it4 hours ago
      Anything can be a microphone:<p><a href="https:&#x2F;&#x2F;people.csail.mit.edu&#x2F;mrub&#x2F;VisualMic&#x2F;" rel="nofollow">https:&#x2F;&#x2F;people.csail.mit.edu&#x2F;mrub&#x2F;VisualMic&#x2F;</a>
  • tamimio5 hours ago
    Yeah I don’t think this will be effective, cameras can be put in certain angles that it can see with being seen, or how police do it, entirely behind clothes or similar fabric where it can see through and identify but not seen even if you’re looking straight at it.
    • dgellow4 hours ago
      <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Perfect_is_the_enemy_of_good" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Perfect_is_the_enemy_of_good</a>