The BBC recently published an exposé revealing that some Chinese subscription sites charge for access to their network of hundreds of hidden cameras in hotel rooms. Of course, this is presumably without the consent of the hotel management and probably isn’t specifically a problem in China. After all, cameras can now be very tiny, so it is extremely easy to rent a hotel room or a vacation rental and bug it. This is illegal, China has laws against spy cameras, and hotels are required to check for them, the BBC notes. However, there is a problem: At least one camera found didn’t show up on conventional camera detectors. So we wanted to ask you, Hackaday: How do you detect hidden cameras?
How it Works
Commercial detectors typically use one of two techniques. It is easy to scan for RF signals, and if the camera is emitting WiFi or another frequency you expect cameras to use, that works. But it also misses plenty. A camera might be hardwired, for example. Or store data on an SD card for later. If you have a camera that transmits on a strange frequency, you won’t find it. Or you could hide the camera near something else that transmits. So if your scanner shows a lot of RF around a WiFi router, you won’t be able to figure out that it is actually the router and a small camera.
The other common method uses a beam of light or a laser to try to see reflections of lenses, which will be retroreflective. The user views the room through a viewfinder, and any light that comes directly back will show up in the view. Despite some false positives, this method will find cameras even if they are not powered or transmitting. Even shining a flashlight, maybe from the same cell phone, around a dark room might uncover some camera devices.
There are a few other techniques. If you assume a spy camera probably uses IR lighting to see you at night, you can scan for that. A good tip is that your cell phone camera can probably see IR. (Test it on an IR remote control.) So looking around with your phone camera is a good, free way to find some cameras. A thermal imager might show hidden equipment, too, although it might be hard to determine if it is actually a camera or not.
You might be thinking: just look for the camera. But that’s not always simple. In the BBC article, the camera was the size of a pencil eraser. Not to mention, a quick search of your favorite retailer will reveal cameras made to look like smoke detectors, stuffed toys, USB chargers, and more. You can even get small cameras that can mount a fake button or screw head on the lens.
Testing
[Project Farm] has a video that tests a few detectors. The problem, of course, is that there are different kinds of cameras. Detecting the test camera doesn’t mean it will detect all cameras. Still, you can get some idea of how effective some detectors are compared to others.
Your Turn?
Given that none of the current ways to detect cameras work perfectly, what would you build to find them? Maybe an NLJD? Or maybe some tech to blind them? Tell us what you think in the comments.
Just hide like the guy on dexter?
Not a show I ever watched, but isn’t “The guy on Dexter” just “Dexter”?
Dexter hunts serial killers. I suspect 110y6 is referring NOT to Dexter, but to the guy on dexter that hides from video cameras, A serial killer the press dub “The Dark Passenger” (Ronald Schmidt), who targets rideshare drivers while wearing an IR LED bedazzled Hoodie to hide from cameras..
Dexter got mad when DeeDee hid cameras in his laboratory.
That’s funny!!
thermal camera works, all of them produce heat
Good luck noticing an OMNIVISION’s OV6948 with a thermal camera. Unless you have a 5-6 figure thermal camera you probably dont have enough resolution to spot anything more discrete than a camcorder tucked behind a plant LOL
if you look at the position of the camera in the BBC video it is extremely well hidden. There is probably a half inch thick ceiling tile beneath it, which will be very high thermal insulation. Basically you would only find that camera if you removed all the ceiling tiles before checking using the current cheap (non-military) IR cameras. Yes you can see temperature changes caused hand prints and feet prints on the surfaces of materials. But seeing through high thermal insulation is not possible with “normal” IR cameras.
It would be interesting to test. Even the optical sensor produces heat, and the heat above the ceiling will leak through the channel to the sensor/lens.
Technically that image is of a sprinkler, not a fire alarm.
Beat me to it.
Also, despite what Hollywood would like you to believe, water will not come spurting out of this if you pull the alarm handle.
But it will if you hang a shirt on it. At least that’s what all the warning labels in the hotels I stay in say.
Well that is a bit more realistic as the only thing holding back the water is a little glass vile and some wax
The glass ampoule (“vial”) contains antifreeze, like alcohol, glycerol, or a glycol, dyed to make it visible.
It will if you shine a laser on it with enough power however
Realistically, if the cameras are just for voyeurism purposes, the most effective counter is to find and proaecute the people selling the video. You can always hide a camera, but you can’t hide a service you’re advertising commercially. Especially if hotel employees are involved, which I am guessing is often the case.
I guess the camera electronics themselves will always produce some (very) faint EM emissions, which will likely change in response to a broght light filckering in a distinctive pattern, even if it’s not transmitting wirelessly. But it still wouldn’t work with the camera turned off.
Yeah. So many governments are trying to force through laws that permit breaking encryption on private messages. But still we don’t have effective system for internationally prosecuting publicly occurring crime where IP address or domain name is known, even though it should be pretty easy.
Governments just resort to blocking illegal websites one-by-one and let the people who run them go on with their business.
What you say is largely not correct.
They constantly arrest people and close down outfits and have extraditions of perpetrators.
Problem is first identifying them and them not being in a country that has no extradition treaty, as well as no trust in the reliability of the often sham justice systems of countries asking extradition (Like the US for example).
But often enough even without a treaty people get extradited after some time.
To answer the title question… I don’t go looking for spy cameras. Most people have 2-4 cameras and 2-4 microphones in their personal belongings listening to them recording and transmitting everything to companies, data brokers and eventually government (foreign or domestic) entities at all times. Accessing public wifi, using dodgy Bluetooth devices, grabbing that dropped USB/1tb sd card on the ground, ouch. I was gotten by a USB drive many years ago, had the company logo on it, was in my mailbox long story…
The most practical way to find cameras is to look around a rented room. First start at electrical outlets, anything plugged in like phone chargers, lamps, etc are first priority. Then work your way to objects that have a vantage point. Stuff 20cm below your waist line is probably a waste of time, unless there are weirdly placed mirrors. Coat hangers on doors, small holes in walls or corners, ventilation systems, big chunky keyholes in door knobs, missing screws, etc. a small roll of electrical tape can go a long way. Maybe it’s not a camera who cares, it’s covered.
Microphones are harder. Magnetic field viewing film does okay for ones that draw enough power. Probably not sufficient for mems devices oh well…
An NLJD would be super cool, hadn’t heard of that, but 10k USD. I am not a criminal, politician, nor a super model it would be real hard to justify that one. I’ve seen people use lasers, and bare bones emf detectors with mixed success. If I had to pick something practical it would just be a flash light and an emf detector. I’ve only ever done quick physical sweeps though, because again, I have to live my life.
The sad truth is, technology is so good now that every single person is at risk for their privacy being exploited at all times to such an extent that there’s no hope at ever being free from such things. I’ve heard of cases where people found cameras and microphones inside their toilet bowls from “friends”…. Ew. Also, people can triangulate wifi and blue tooth really good now, not the same as videos, but your actions can be deduced pretty well…
Any idea how long a phone would last if it was really sending back audio and video to the mothership all the time?
Not as long as users would like. But it doesn’t have to do it all the time, it also doesn’t have to do it with high integrity. But checkout “active listening”, a lot of denials but the company still exists and the technology was disseminated to major ad groups. Exfiltration via text is becoming more and more possible due to speech to text as well.
You suggest it would not be practical, but people have tons of always connected apps like whatsapp and messengers andsoforth and are receiving constant updates and watch videos all day, and stream audio to their BT earbuds and it does not kill their phone in an hour.
I bet you could stream constant audio in a low bitrate codec 24/7 without anybody noticing in terms of power drain.
That may be true, to some degree – and you might also not want to be streamed to random people on the ‘net while making out in hotel rooms? The BBC piece also said that Chinese folks have started just assuming the worst and rigging up tents or canopies around their beds in hotel rooms, which must make for some extra luggage, but is a simple fix.
Simple. Strip to the birthday suit, and listen for the exploding hardware.
Exactly! I’d shake my junk at any suspected camera – CLOSEUP! Check for ER admissions with uncontrollably vomiting or ophthalmologists reporting sudden onset blindness. I have no illusions about the appearance of the corporeal shell I inhabit.
Just spray paint the room after you checked in
/\ This. If you find a camera, spray painting is the least the hotel will accept from you (the alternative being to get into a public trial and the news). Choose a very specific color, ideally with some lacquer or varnish (it’s harder to remove), like vomit or blood and write “camera” with an arrow to the lens, so the other guest will directly spot the camera, saving their time. That way, the hotel manager (if they are innocent) will be motivated to find out who hide the camera in the first place and fire them (likely with a trial for damages), and if they are guilty, will realize that it’s not beneficial for them to repaint the room after each guess.
Uhm, you do realize that there are hundreds of millions or even several billion people who are really paranoid right? And that most people are a bit thick, and will take anything to be a camera, and if your advise was followed all the hotels in the world would be full of paint from paranoid maniacs mistaking random things for cameras.
Or in other words: Expect to be billed for damages and never set foot in the affected chain again.
During the pandemic, a friend’s spouse had me spend an hour remotely troubleshooting her laptop’s webcam. It was dead but the microphone worked – the drivers loaded and the system “saw” a live webcam.
After an hour, I had her physically inspect the laptop while I was watching on the phone.
He had jammed black wax into the camera’s inset.
When confronted by an irate spouse and friend he explained that he was afraid hackers could spy on him, thereby stealing the incredibly valuable data available by looking at a 75 year old high functioning alcoholic doingUSA Today crosswords and surfing for pr0n.
We don’t talk any more.
But really, as someone said, I’m not a spy, billionaire or supermodel.
If people want to spy on me in a hotel I have better things to do than look for hidden cameras. Knock yourselves out.
If I’m in certain countries. I’m also going to assume that my phone and any other devices will have already been compromised at a root level and that my VPN is worthless.
Welcome to the 2nd quarter of the 21st century. Same as it’s been for 100+ years. People spy on other people.
i just want a cheap and easy way to find out which of the 30 devices in my livingroom beeps once every couple weeks or so
(actually, i haven’t heard it in years so i guess it went away)
The NSA decided that your life was too boring and so they moved on! 🤣
Rewinds warm memories of the last spring cleaning.
Kids toys with AAs forgotten inside … thought to be discharged, just to suddenly spring to life in the middle of the night due to sudden draft wind in a basement … cats were known to suddenly get up at ~3am and start scratching at the basement door thinking it is a snake or a mouse … no, just Bob the Builder excavator revving the engine and promptly expiring : -]
True story – my son had this Abrams Tank toy long forgotten and sitting at the bottom of one of the Goodwill-slated boxes. Out comes the basement draft, the pile above tank shifts and we suddenly hear “ra-ta-ta-ta” – “I am taking heavy fire!” and suddenly cuts off. Fun :-]
I am afraid those spying on me run a real risk of being literally bored to death. Pity, Season Two will never come.
This is a common misconception. Do you have a job? Could that job have any utility to anyone for nefarious purposes? Do you have any form of hobby equipment that could maybe possibly by extreme extrapolation be used for something not good? Then yea you are worthy of 24/7 every network packet sent surveillance just like all the rest of us. The bar for scammers is so low they just send random emails vague blackmail threats. Imagine if they had anything to go off of.
Not trying to be spooky but as I’ve gotten older I’ve come to realize there is a surprisingly low bar for anything and the types of people who do this stuff are typically deranged. The few creepy kids who stalked people and got bullied in every graduating class end up going pro at some point.
If a scammer said to me “comply with our requests or we’ll release these compromising images to your loved ones!” I’d say go for it, it’ll be more traumatizing for the recepient than me and good for a laugh.
But I suspect the scammers would already be traumatised by what they see and too busy dealing with with their own mental health to actually make any threats….
Having said that, I do use good privacy practices where possible, but more for the protection of others than myself…. hahaha
Great place for a camera is in a WiFi router. They sit up high on a shelf with blinkenlights, RFI, and wires covered with slots 3D logos and such.
I remember a story about high-powered LIDAR units damaging camera sensors, I wonder if a “lidar bomb” could be made that just sweeps one of those over-powered laser pointers around the room for a few minutes while you avert your eyes would be a compact and portable solution.
Camera destruction is challenging as well. Commodity high power lasers and lidar can damage the sensor elements in cameras. The key word is damage. Maybe a few lines in the ccd go out, or some ghost pixels form. It would take a direct hit for a somewhat prolonged period of time to really do the trick.
In cases like this, it’s easier cheaper and safer to just cover the camera with electrical tape and notify authorities. But it’s fun to think about for sure.
I wonder if there are other forms of obfuscation that could be used though. People have demod wearing buckets of ir LEDs to saturate the detectors. Maybe there’s a way to get some ir led strips along walls that could do similarly for securing a room. It seems impractical.
I was wondering about something similar – one of those laser soot cleaners. It wouldn’t leave much in the way of visible damage, and you could cover the entire room pretty quickly.
The problem is that the laser pointed at the camera only damages the spot that the laser is coming from in the image. Unless it’s a really high powered welding laser or something that can set things on fire. Laser damage to cameras is like pointing old tube cameras at the sun, and getting an afterimage. The camera is ruined for making commercially viable video, but still fine for surveillance.
“ A good tip is that your cell phone camera can probably see IR.”
This was true maybe 15 years ago, but I think you’ll find any decent phone now has an IR filter on the camera. Otherwise it’ll take crap shots outdoors.
Depends on the IR. Cameras can see the IR from remote controls and what’s used for camera “night vision” just fine.
And what is used for cameras depends on what the owner decided to buy, if they buy the right wavelength and use a CCTV cam without a filter then they could light up things without a normal phone camera seeing it I fear.
Maybe you should try it out before making such confident pronouncements.
Thermal image for things that are warm and shouldn’t be – like a random point in the wall. If it’s warm and has an RF signature and shouldn’t (This gets more difficult as everyone adds remote/online capability to just about everything). If it’s warm and RF-ey, does it have something like a lens (which can be the size of a pin-head)? If all of these conditions are met, blue tape over the “lens” is your friend. Then play back something suitably impossible and let them wonder over the sounds they’re getting.
If you think you really can detect all cameras then look into the DARPA project called REVEAL: Revolutionary Enhancement of Visibility by Exploiting Active Light-fields.
Is there a way to destroy them? Possibly use a device to emit a very strong bright light, x-ray, infrared, ultraviolet, etc.? Just place the device in the middle of the room, set the timer, exit the room and camera destruction. Who’s going to complain?
Ordinary folks with nothing to show or hide, can simply assume that a camera is watching you , a microphone listening, and act accordingly. I can’t think of any of my family trips and stays in hotels where anyone could have seen or heard anything that would not have bored them out of their mind.
With AI today and the garbage media created by AI everyday, people soon will not care at all about the cameras around. Today people spent only a few seconds for each video “reel” online.
We will not believe and not care about any photo or video we see around, no matter it was real or A.I.
Probably in a few years we cannot provide a video footage as an evidence in the court.
Media is dead.