Do Security Cameras Record All the Time?

Which cameras record continuously, and which do not

A camera can only record continuously if it is awake continuously, and a camera is only awake continuously if something is feeding it power. That single physical fact sorts the whole category: wired and PoE cameras can do 24/7, and battery and solar cameras cannot, no matter what the app settings offer. Reolink states it plainly in its own documentation, and it is not a limitation any firmware update will remove.

What you actually miss when a camera sleeps

Event recording is not simply “the same footage with the boring parts cut out.” Three things are genuinely absent, and they are the three complaints people have about battery cameras six months in.

The start of the event. A sleeping camera needs to be woken by its motion sensor, boot its imaging pipeline and begin writing. Some cameras hold a short rolling buffer to recover part of that gap; many do not, and the clip begins with the subject already in frame.

Anything static.A car that was already parked when the camera went to sleep generates no motion, so it appears in no clip. If the question you will ask the footage is “when did that van arrive,” event recording may genuinely not be able to answer it.

Slow or distant movement. Passive infrared sensors respond to heat crossing detection zones. Someone moving slowly, at the edge of the zone, or behind glass can fail to trigger a wake at all. Turning sensitivity up trades this for a notification every time a cat walks past, which is how most people end up ignoring their alerts.

What 24/7 recording needs

Three things. Constant power, which for an outdoor position usually means PoE rather than a mains lead, because one cable carrying power and data is easier to run than a weatherproof supply — the comparison is in PoE versus Wi-Fi. A destination with room: a large card, an NVR, or a local base station. And a decision about retention, because continuous recording does not stop when the disk fills — it overwrites the oldest footage, and how far back you can look is a function of disk size and bitrate.

The retention arithmetic

You can work out retention yourself from two numbers, and it is worth doing before you buy a drive. Take the stream bitrate in megabits per second, divide by eight for megabytes per second, and multiply out. At a 4 Mbit/s bitrate — a reasonable mid setting for a 2K camera — that is 0.5 MB/s, which is 1.8 GB per hour and about 43 GB per day per camera. A 2 TB drive therefore holds roughly 46 days from one camera, or about 11 days from four.

Push the bitrate to 8 Mbit/s for more detail and the numbers halve: about 86 GB per day per camera, so roughly 23 days of one camera on the same 2 TB drive, or under a week from four. This is why the recorder, not the camera, is the component that decides what a continuous system can actually do, and why we rank systems on the recorder in our camera system rankings. Those figures are arithmetic from a bitrate you choose, not a measurement of any particular model.

The middle ground most people should use

Continuous and event recording are not mutually exclusive on a wired camera. Most recorders will capture a continuous low-bitrate stream for the record and flag motion events within it for quick review, which gives you a complete timeline and a short list of things to look at. If your camera and recorder support it, this is almost always the right configuration: you keep the ability to answer continuous questions without scrubbing through fourteen hours of an empty drive.

Where the footage lands still matters more than the mode. A continuous recording on a vendor cloud is a continuous bill, and a continuous recording on your own drive is a one-off purchase — the full argument is in local storage versus cloud, and the five-year cost comparison is in what the plans cost.