It looks for infrared light. This will only detect a small subset of surveillance cameras that actively use infrared light for illumination. There are tons of dome cameras, and such that don't use infrared light.
It's a cool art project.
There was a research paper I found on detecting hidden cameras that emitted high power IR light, and looked for reflective sources. Potentially, you could listen to EM noise, and then introduce visual noise to the environment. It turns out, this is a hard problem to actually solve.
I have read - and I'd love to have this confirmed or refuted - that pretty much all those cameras are tuned somewhat into the IR so that they can still do useful surveillance in low light situations.
My ~solution~ hack is to fasten a couple of small IR LEDs into my hat and flood the cameras with lots of lights ;)
My ~solution~ hack is to fasten a couple of small IR LEDs into my hat and flood the cameras with lots of lights ;)
You need to consistently be at the proper angle for this. That and once again, it's only useful for the most primitive cameras that have a constant IR level.
cameras are sensitive to IR and usually have a filter to block it, since it it usually unwanted. you'd need extremely and impractically powerful IR lights to do anything useful.
This post illustrates is the problem with HNs "original title" policy: it lets inaccurate linkbaity titles from sketchy publications (including the modern Atlantic) get repeated on a more(?) reputable site like HN.
This is a creative art project. Obviously, it doesn't work, and cannot work as designed. Most consumer night-vision cameras emit near-infrared light with LEDs at around 750-900nm, which is the wavelength this spaulder is designed to pick up. This is the same wavelength of EM radiation your TV remote uses. If your phone camera does not have a filter for IR light, you can see this kind of radiation as a white glow through your phone.
Cameras generally emit IR only while in darkness. Sunlight, or even incandescent lightbulbs, will emit so much infrared light that any nearby security cameras would be blotted out.
A functional 'security spaulder' device would need to be far more complex. Maybe a combination of IR, network packets, and other indicators would work.
It's a cool art project.
There was a research paper I found on detecting hidden cameras that emitted high power IR light, and looked for reflective sources. Potentially, you could listen to EM noise, and then introduce visual noise to the environment. It turns out, this is a hard problem to actually solve.