If you don’t know much about motion sensors, you might assume they have to involve some kind of camera.
Since they’re literally ‘detecting motion,’ then they have to be able to see the movement. So a camera must be involved, right?
The ‘motion detector’ is a bit of a misnomer.
They don’t detect motion. Instead, they notice changes in the radiation in their field of view.
So, camera or not?
Motion sensors don’t use a camera. Depending on the type, they work using either a passive receptor or an active emitter (sometimes with a separate receiver). Some cameras will have motion sensors attached, but the motion sensor works independently to control the camera.
To make it a little bit clearer, let’s take a look at:
- How motion sensors work
- How to tell if a motion sensor has a camera
- Whether you can buy cameras with a motion sensor attached
Do Motion Sensors Use Cameras To Detect Movement?
Motion sensors will use either a passive or an active sensor.
Passive sensors mean that they just detect things in their field of view. Active sensors ‘actively’ send out a signal, either to a separate receiver or a signal designed to bounce back to a receiver on the motion sensor.
There are no cameras involved at any point. Instead, motion sensors rely on different kinds of radiation (which sounds scary, but it’s perfectly safe and normal).
Most motion sensor lights use a PIR sensor – a passive infrared sensor.
It’s passive, so it doesn’t emit anything. Instead, it looks for changes in infrared radiation typically caused by heat, such as our body heat.
That doesn’t mean it’s a thermal camera. It’s just a sensor that reads an area and is triggered when something changes.
No images are captured in any way.
How To Tell If A Motion Sensor Has A Camera?
Because motion sensors don’t use cameras, there’s no need to check whether they have one.
A motion sensor is usually a pretty discrete object that is either attached to light or is situated close by, directed to look over a wide area from a high angle.
That doesn’t mean you won’t ever see a camera next to a motion sensor.
But that’s not a camera that the motion sensor is using. Instead, the camera is using the motion sensor…
Can You Buy A Motion Sensor With A Security Camera?
Yes, you can buy a security camera that uses a motion sensor.
It’s really important to make that distinction clear. However – if you spot a camera with a motion sensor, the sensor isn’t using the camera to detect motion.
Instead, the camera uses the motion sensor to know when it needs to switch on a record.
Two main types of cameras use motion sensors.
They’re both similar and for similar purposes, but they’ll look slightly different. And they are smart doorbells and security cameras.
Smart doorbells are those newer doorbells that have a camera built-in.
The idea is that when someone presses the doorbell, you can connect to the camera live to talk to the guest.
If it’s a delivery person, you could ask them to leave a package somewhere safe, or if it’s a friend, you can explain that you’re not at home.
They also come with a motion sensor to let you know if someone is approaching.
And so they essentially act as a type of security camera because they can let you know if someone is looking around your home without planning on ringing the doorbell.
They use the same kind of PIR sensor as most lights, so they work just as well at night, making them very effective.
They’ll ping your cell phone with a notification so that you can watch live and record any motion for you to view later.
You’ll sometimes need to pay for a subscription plan to keep recordings.
And security lights work in the same way.
They can have a motion sensor that activates the camera to start recording whenever motion is detected.
Some smart security cameras will also have a built-in security light to illuminate the space. At the same time, they record and a microphone so you can chat with anyone you see.
Others also come with a siren that you can activate remotely to spook any intruders.
Why Are Motion Sensor Cameras Useful?
There are two main reasons why cameras with a motion sensor are helpful.
The first is cost.
They might be a little more expensive than a traditional security camera upfront. Still, they don’t have to record 24/7, and video footage (especially clear HD footage) takes up a lot of storage space, which translates into a high cost.
You don’t have to worry about having huge file backups or expensive cloud storage solutions by only recording when there’s motion.
Instead of 24 hours of footage per day, you might have less than 30 minutes in clips.
The second reason is specific to smart cameras, and that’s the live view function. Without a motion detector, you’ll never know if someone was trying to loot you.
They wouldn’t be stopped; instead, you’d only be able to use the footage afterward to try to identify them (and you’d have to spend a lot of time searching to find it).
With a motion sensor-activated camera, you’ll get live notifications that mean you can see what’s happening as it’s playing out, letting you call the police if you need to.
Or even if it’s just animals trying to break into your trash, you can stop them with a light or a noise instead of dealing with the clean up the next day.
Also read: Can Motion Sensor Lights Be Battery Powered?
Anyone who isn’t tech-savvy could easily think that motion sensors must use a camera.
However, they use much simpler and more cost-effective options that are potentially even more reliable than a camera that relies on being able to see.
So, if you see a camera with a motion detector, remember that it’s the camera using the motion sensor and not the other way round.
And if you’re considering a home security system, then definitely opt for one that does use a sensor.
This way, you’re updated with live goings-on around your home.
Do you have any questions about motion sensors?
Has your motion-detecting security camera ever picked up something interesting or amusing?