It's understandable why you might be concerned that drones could spy on you, considering how many of them you can see nowadays. But can they see inside your house?
Drones aren't able to see inside your house unless it's through the windows, as the camera technology required to see through walls doesn't exist yet, even in the case of military use.
So don't worry; your privacy is well protected from the peeking of consumer drones for sure.
However, keep on reading to see what technology can stand a chance to detect objects and people behind walls and even inside homes.
In my experiment with how far a drone can see at night, I have also noticed how easy it is for a drone to see through a house window and detect the drone before it can get close enough to spy on you.
Drones can see through house windows if they are close enough or have an advanced zoom camera. However, before they get in a proper range, most drones make noticeable noise and are easy to spot.
In my experiments, even with very silent drones like the DJI Mini 2, it's tough to see indoors unless you are very close to the window or the drone flies in very close proximity, which makes it noticeable.
However, if you do not have your blinds on, there is still a possibility of losing your privacy to more advanced drones with powerful zoom cameras.
Here's a test I made to see how well a drone can see through windows in daylight:
As you can notice, even if the inside is well lit (I did my best), the drone still can't see what's happening inside unless you get close to the window. It's also very easy to hear the drone up to 20 meters, and I used one of the most silent drones available (a DJI mini 2).
A vital privacy concern would arise if drones could see through walls. But is there any technology we know of that gets even close to that?
No, drones cannot see through walls with standard cameras as the light from indoors cannot penetrate them. The latest technology that comes close uses wifi signals that bounce from indoor objects to give a rough outline.
You can see the results of this technology in the following video, using two drones with two large antennas to both capture and release wifi signals from two angles.
This is an example of a 3d image of a completely unknown area behind walls that resulted exclusively from using only wifi RSSI measurements.
One of the drone reseases the wifi signal while the other captures it at a different angle, resulting in a 3d map creaded by the signal strenght.
As you can see, the setup is bulky and requires extreme precision to get a very rough result.
In the image below, you can see that the objects inside don't correspond entirely in terms of shape, as the bricks found inside the walls were square, and the final image was blurry and round.
Even so, this technology has a great potential in the future to become the closest thing to actually seeing through walls.
It is easy to grasp why drone cameras can't yet see through walls, but will curtains save your privacy from prying eyes?
Standard consumer camera drones cannot see through opaque window curtains; However, more advanced thermal cameras can detect human figures behind thin curtains.
Here are some pictures I took of some blinds from my drone at different distances, and a normal drone can't see anything behind them:
Blinds are still effective even for blocking thermal camera drones from seeing indoors, and the thicker the curtain, the fewer chances there are to see through them.
As you can see in the image below, even a thin shower curtain can block a good part of the heat radiation behind it.
Infrared is a technology that has been explored for seeing through otherwise opaque objects, but there are specific requirements.
As you can see in the video below, only certain plastics and infrared filtering material can be seen through with an infrared camera but not through walls for sure.
While drone technology has evolved exponentially, there is still no solid concern that drones can see what you're doing between closed walls, and there's no expectation you should be worried soon either.